prepared by: forest products research and development ...basic working stresses for grouped...
TRANSCRIPT
ITTO
INTERNATIONAL TROPICAL TIMBER ORGANIZATION
Distr
GENERAL
PPR 52/99 (1)
Original: ENGLISH
DEVELOPMENTAND IMPLEMENTATION OF STRESSGRADING RULES FOR TROPICAL TIMBER IN THE PHILIPPINES
PRE-PROJECT REPORT
Prepared by:
Forest Products Research and Development InstituteCollege, Laguna, Philippines
February 1999
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ACKNOWLEDGEMENT
The authors would like to express their sincere appreciation for thesupport given by the International Tropical Timber Organization and themanagement of the Forest Products Research and Development Institute tothis pre-project study. Acknowledgement is also due the following individuals:Dr. Isabelita M. Pabuayon of the University of the Philippines at Los Bailos forher guidance in the Economic and Marketing studies, Mr. Ron Arithony of theEngineering Data and Management in Colorado, Dr. Robert Leicester ofCSIRO Melbourne, Mr. Omar Khaidzir and Dr. Abdul Rashid of ForestryResearch Institute of Malaysia for providing invaluable information on thetechnical aspect; and the organizational assistance provided by the PhilippineWood Products Association, the Association of Structural Engineers of thePhilippines, the Philippine Institute of Civil Engineers, the Wood Science andTechnology Department of the University of the Philippines, PANELCORP,the Department of Public Works and Highways, the Task Force on HousingTechnologies of the National Housing Authority, the Committee onAccreditation of Innovative Technologies of the Housing and UrbanDevelopment Coordinating Council, the Subdivision and Housing DevelopersAssociation, the Philippine Domestic Construction Board, the EcosystemsResearch and Development Bureau and the Forest Management Bureau ofthe Department of Environment and Natural Resources, TIPI Wood ProductsCorp. , Top Forest Developers, Inc. , Industries Development Corporation,Maple Resources Development, Inc. and Provident Tree Farms, Inc.
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The benefits of stress grading lumber for structural use can be realizedand stress grading rules can be implemented under assumptions of productacceptability, market demand, sustainability of raw materials, and profitabilitof adopting the technology. Acceptability, on the part of technologimplementors, can be addressed by selecting a technicalIy and economicalIacceptable stress grading method, and eliminating information and culturalbarriers to enhance the awareness of consumers on the benefit of stressgrading and ensure market demand for stress graded lumber. A sustainablesupply of raw materials, whether from local production or imports, will allowproducers to sell stress graded-lumber that is competitive with alternative non-wood construction materials. On the part of investors and/or producers,stressradinwillbdtd I 'stress grading will be adopted as long as incremental profit associated withstress grading remains positive. Definitive conclusions on the profitabilit ofstress grading can be made with more in-depth and exhaustive examinationof the market, prices and cost structure.
The biggest market for structural lumber currently is in the constructionof residentials and small buildings or in general, those limited to a hei ht ofless than 10 meters. It is important to note that, whereas the Phili ines iscurrently experiencing a construction boom and will continue to do so in thenext 15 years, the national housing backlog needs to be addressed morestrategically. Codes and standards in the utilization of wood as a constructionmaterial must be enforced as rigidly as those for concrete and steel. Lumberstress grading can be an effective and workable tool in achieving thispurpose.
The development and implementation of stress grading rules in thePhil, ,,,',,, I " 'Philippines will be a long process, hence initiatives should be placed in motionimmediately. Massive information campaigns should involve linkages with allconcerned sectors, meetings, dialogues, mass media exposures, trade fairs,communication materials production and dissemination and academiccurriculum integration. A full-scale project to follow up and extend the workstarted in this pre-project, and to actualize the development andimplementation of lumber stress grading in the country is recommended.
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EXECUTIVE SUMMARY
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AcknowledgementExecutive SummaryList of FiguresList of Tables
List of Appendices
TABLE OF CONTENTS
Chapter, INTRODUCTION
1.1 THE PRESENT SYSTEM OF SORTING AND PRICINGLUMBER IN THE PHILIPPINES
1.2 THE PRE-PROJECT STUDY
1.3 OVERVIEW OF PRE-PROJECT REPORT
Chapter2 TECHNICAL REVIEWOF LUMBER STRESS GRADINGSYSTEMS
2.1 INTRODUCTION
2.2 STRENGTH GROUPING
2.3 STRESS GRADING METHODS
2.3. I Visual Stress Grading (VsG) Method2.3.2 Mechanical Stress Grading (MSG) Method
2.32. I Bending Type NDE machines
2.3.2.2 Other Types of NDE machines2.3.3 Other Stress Evaluation Methods
2.3.3.4 Proof Loading
2.3.2.2 In-Grade Testing
2.4 DEVELOPMENTS OFLUMBER STRESS GRADING INVARIOUS COUNTRIES
2.5 DEVELOPMENTS OF LUMBER STRESS GRADING INTHE PHILIPPINES
2.6 IMPLICATIONS OF TECHNICAL DEVELOPMENTS ONTHE OPPORTUNITIES FOR LUMBER STRESSGRADING IN THE PHILIPPINES
Chapter3 DEMAND AND SUPPLY OF TROPICALTIMBER FORCONSTRUCTION PURPOSES IN THE PHILIPPINES:IMPLICATIONS FOR LUMBER STRESS GRADING
3.11NTRODUCTION
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3.2 USES OF WOOD IN CONSTRUCTION
3.3 THE PHILIPPINE TIMBER SITUATION
3.3. I Natural(Residual or Second-Growth) Forest3.3.2 Timber Imports3.3.3 Tree Plantations
3.3.4 Available Volume of Lumber forthe ConstructionSector
3.4 LUMBER SUPPLYAND DEMAND SCENARIO FORTHECONSTRUCTION INDUSTRY
3.5 IMPLICATIONS OF LUMBER SUPPLYAND DEMANDON STRESS GRADING
Chapter4 EXPLORING THE ECONOMIC FEASIBILITY OF LUMBERSTRESS GRADING IN THE PHILIPPINES
4.11NTRODUCTION
4.2 METHODOLOGY
4.2. I Conceptual Framework: The Economics of StressGrading
4.2.2 Analytical Approach4.2.3 Sources of Data
4.3 RESULTS AND DISCUSSION
4.3. I The Present Pricing and Marketing System4.3.2 Alternative Approaches in Assessing the Economic
Feasibility of Stress Grading4.3.2.1 Stress Grading as an Additional Operation
in the Sawmill Using Partial BudgetAnalysis
4.3.2.2 Stress Grading as an Investment Optionfor Sawmillers Using Investment Analysis
4.3.2.3 Marketing Margin Analysis for AssessingBenefits and Costs for Lumber Traders
4.3.4 Factors Affecting the Viability of Stress Grading4.3.4.1 Demand
4.3.4.2 Sustainability4.3.5 Potential Economic Benefits and Costs of
Implementing Stress Grading in the Philippines4.3.5.1 Benefits of Stress Grading4.3.5.2 Costs of Stress Grading
4.4 IMPLICATIONS AND RECOMMENDATIONS
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Chapter5 MARKETASSESSMENTAND STRATEGIES ON THEIMPLEMENTATION OF STRESS GRADING RULES FORTROPICALTIMBERS IN THE PHILIPPINES
5.11NTRODUCTION
5.2 REVIEW OF LITERATURE
5.3 METHODOLOGY5.3. I Market Potential Analysis
5.3.2 Marketing Problem Characterization5.3.3 Market Entry Modes/Strategies
5.4 DISCUSSIONS
5.4 I Market Potential Analysis5.4.1.1 SizeNolume of Stress Graded Lumber
5.4.1.2 Sustainability of Raw Material Supply5.4.1.3 Interplay of Favorable Factors
5.4.2 Marketing Barriers Characterization5.4.2.1 Culture and Tradition
5.4.2.2 Price Structure
5.4.2.3 Lack of Enabling Rules. Regulations,Policies and Laws
5.4.2.4 Uncertain Supply of Stress-Graded lumber5.4.2.5 Lack of Education and Promotion
5.4.3 Market Entry Modes and Strategies5.4.3.1 Linkages and Networking5.4.3.2 Concept and Product Promotional
Schemes
5.4.3.3 Product Entry/Marketing Channel
5.5 IMPLICATIONS AND RECOMMENDATIONS
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CHAPTER6 CONCLUSIONSAND RECOMMENDATIONS
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REFERENCES
APPENDICES
THE PREPROJECTSTAFF
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FigureNo
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Schematic representation of the lumber sorting system inthe Philippines
The basic elements of grading (Leicester 1981)Schematic illustration of the sorting process for singleand mixed species (Leicester 1984)A diagrammatic representation of the CLT-I stress
grading machine (Muller 1966)A diagrammatic representation of the Stress-0-Matic(SoM) grading machine (Muller 1966)A diagrammatic representation of the Microstressgrading machine (Muller 1966)The principle design of the Computermatic gradingmachine (BOStrom 1985)The TRIMAG mechanical stress gradingmachine(Vinopa11985)The principle of the Cook Bolinder stress gradingmachine (BOStorm 1994)The principle design of the Finnograder stress gradingmachine (BOStrom 1994)The principle of the Sylvatest(BOStrom 1994)The Schematic illustration of the proof grading procedureThe NTIR high-speed proofloader for battens (Vinopal1985)The NTIR proofloaderforlaminated beams (Vinopal1985)Schematic diagram of simple stress grading machine at
FPRDl used in initial investigations of the concept onspecies independent stress grading machine
Product and information flow for lumber produced in thePhilippines
Target outputs and organizational linkages of the threecomponents of the proposed project on thedevelopment and implementation of stress gradingrules for tropical timber in the Philippines
Flowchart of activities of the proposed project on thedevelopment and implementation of stress grading
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LIST OF FIGURES
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TableNo
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Comparative prices of lumber in the Philippines (March1997)
Basic working stresses for grouped Philippine structuraltimber speciesVolume of timber in Philippine commercial forests, 1996Local log production in the Philippines, 1987-1996Log production by type of timber license in thePhilippines, 1996Production of processed wood products, 1987-1996Imports:logs and lumber, 1987-1996Area reforested by the government and private sectors,1987-1996
Wood production from existing forest plantationsWood production from new plantationsActual(1987 -1996) and projected (2000-2015)lumber
supply (availability) and demand of housingconstruction in the Philippines
Estimating the change in profits for a given volume oflumber as a result of stress grading
Comparative cost and return structure of lumberproduction, with and without stress grading
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LIST OF TABLES
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Questionnaire for producers and tradersQuestionnaire for consumers and end-users
Information brochure on lumber stress gradingProgram of the FPRDl-ITTO Consultative workshop on
lumber stress gradingParticipants of the FPRDl-ITTO Consultative workshop
on lumber stress grading and Project Staff of ITTOPPD 1296
UNIDO Simplified stress grading rules fortropicalhardwoods
UNIDO grade ratios for structural no. I and 2 forhardwoods
Limits of defects in joists and planks for seasoned lumber(NSCP 1972)
LIST OF APPENDICES
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Recommended working stresses for some Philippinestimber(NSCP 1992)
Minimum strength group limits for grouping Philippinetimber species(NSCP 1992)
Recommended end used for five strength groups ofPhilippine timber(Tamolang et. at .1995)
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Chapter,I
INTRODUCTION
THE PRESENT SORTING SYSTEM AND PRICING OF LUMBER INTHE PHILIPPINES
Integrated mills in the Philippines sort logs according to their mostsuitable use. Through visual inspection, log graders determine whether logswill be processed into plywood or lumber. Logs intended for plywoodproduction should idealIy be free of knots and splits. Logs riot suitable asplywood material end up being processed into lumber.
In general, there are four steps in saw milling: head-sawing, re-sawing,edging and trimming. It is in the final step, when the boards are cut to theirfinal size, that grading for defects takes place. As the board passes throughthe conveyor, an experienced grader examines it for knots and splits anddetermines the best cut to eliminate the defects and maximize recovery. Aftertrimming, the boards are inspected further for defects. Boards that pass thisinspection go to the stacking area for bundling; otherwise, they are re-sawninto shorter and/or narrower boards to eliminate the defects.
This system has evolved in response to market dictates and changesin the local wood industry situation. Figure I, a schematic representation ofthe grading system, is a synthesis of the information gathered from a surveyof sawmills and lumber dealers conducted in this pre-project study.
In the local market, the preference for local wood over the importedones has given rise to two major groupings --- the local species and theimported species ~-- the latter group, a consequence of the wood industry'sreaction to the logging ban. The imported species are further distinguishedinto either Brazilian or Malaysian timber. These groupings resulted from themarket's preference for Brazilian timber, which has been found to be easier towork with than the much denser Malaysian woods. Furthermore, Malaysianspecies imported by the Philippines is riot quality assured as it has beenreported that grading for export on the basis of strength is not popular inMalaysia (Collins and Ashaari1990). Most exported Malaysian hardwoodsare appearance graded, the remnants of which are stress graded for theirlocal use as framing, falseworks and frameworks in temporary structures.
Local species can be further distinguished between: I) the commonhardwoods, and 2) the LKS and miscellaneous species. Like the imported
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species, the second group is a relatively recent class which, in all probability,arose from the efforts of the market to deal with a decreased supply situation.
Sub-classes forthe common hardwoods, on the other hand, seem tohave developed directly from traditional market preferences. There are twodistinct hardwood groupings. One group has color as a factorfor segregation,and the other group has strength property as a factor. When color orappearance is the major consideration for a particular end-use, choices rangefrom the "red" species such as red lauan (Shorea negrosensis), tanguile(Shorea polysperma), mayapis (Shores squamata), and inariggachapui(Hopea acuminata), to the lighter colored white lauan (Pentacme contorta)and bagtikan (Pareshorea plicata). These species are used for both furnituremanufacture and construction.
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LUMBER MIX IN THE MARKET
LOCALSPECIES
DIPTEROCARPS
RED &WHITE
LAUAN, TANGUILEMAYAPIS,MANGGACHAPUl
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LESSERKNOWNAND
MISCELLANEOUSSPECIES
YAKALGUIJO
IMPORTEDSPECIES
Figure I Sorting and Grading System for Lumber in thePhilippines
BRAZILIANTIMBER
SPECIES
Yakal (Shorea astylosa) and guno (Shorea gutso), also dipterocarps,are grouped separately from the red-white groupings. Traditionally, these are
MALAYSIANTIMBER
SPECIES
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prime species favored for use in construction requiring certain strengthrequirements.
Prices of lumber vary between species. Based on the March 1997Metro Manila Construction Materials Prices and Indices survey, premiumspecies such as yakal sell from P45.00 to R55.00 per bdft. Comparatively,the price of tanguile, red lauan and white lauan is one-half lower, ranging fromP24.00 to P28.00 per bdft. Imported species are priced aboutthe same asthe second group and are thus positioned as direct substitutes of thesetraditionally favored local species (Table I).
Table I. Comparative Prices of Lumber
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Tanguile, red and whitelauan
Imported species
Species
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*Metro Manila Construction Materials Prices and Indices, March 1997.**From interviews of lumber dealers, April - May 1998.
It is evident that present lumber grading system for lumber in thePhilippines is more appropriateIy referred to as "appearance grading" or inLeicester's (1984) definitions, "rough sorting", rather than stress grading. Thesorting process in the mills makes no reference to the Visual Grading Rules inthe National Structural Code of the Philippines (see Appendix 8). Althoughthe grading method accounts for strength-reducing characteristics such asdefects, lumber in the market is generally priced according to species andsize. Its perceived structural value is secondary. It is not surprising thatalternative construction materials such as steel and concrete have replacedsome markets for lumber and other wood products specially in houseconstruction. The marketfortrusses, beams, window and window frames, aswell as door frames of residentials and other small buildings used to bedominated by lumber from premium wood species. With the diminishingsupply of premium species, the lack of quality of substitute imported species,and the questionable pricing structure, consumers opt to use steel ahd othersubstitute materials which are sanctioned by the Bureau of ProductsStandards (PS).
The existing annual demand forthe low-cost housing in the Philippinesis placed at 600,000 units. The current administration has targeted to build1.15 million affordable homes between now and the year 2004 and it haswelcomed the current inflow of industrialized construction systems whichestablished some demand for quality-assured lumber in addition to the
Price per bdft.
p 45.00-55.00*
p 24.00-28.00*
p 25.00-27.00**
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existing market. Based on experience in developed countries, lumber is themost workable material for light frame and panelized structural systems. Tomeet this demand, a lumber stress grading system appropriate for our localsawmilling operations and structural uses must be developed andimplemented. Hence, this pre-project study on the development andimplementation of stress grading rules fortropicaltimber in the Philippines.
1.2 THEPRE-PROJECTSTUDY
The general objective of this study was to assess the feasibility ofdeveloping and implementing a unified lumber stress grading system for thePhilippines. Four interrelated studies having specific objectives wereimplemented.
Study I Technical review of lumber stress grading methods
International developments on lumber stress grading, as well as thosein the Philippines, were reviewed forthe purpose of identifying an appropriatestress grading system for the Philippine situation. Specifically, thiscomponent aimed to:
a. Review the developments of lumber stress grading in various countriesb. Determine the most appropriate lumber stress grading system for the
Philippine situation
c. Assess the technical developments of lumber stress grading in thePhilippines and identify appropriate steps fortowards its implementation.
Study 2 Lumber supply and demand for construction purposes in thePhilippines:Implications for stress grading
This component was undertaken to assess the wood supply anddemand situation in the Philippines. Specifically, the objectives were to:a. Generate information on lumber supply and demand situation in the
Philippine construction (housing) industry; and
b. Determine the implication of supply and demand trends on the prospectsof stress grading.
Study 3 Exploring the economic feasibility of lumber stress grading fortropical timber in the Philippines
This component explored the economic framework for determining thefeasibility of stress grading lumber in the Philippines. Specifically, the studyattempted to address the following objectives:
a. To describe the present system of lumber production, grading andmarketing and determine the points where stress grading may apply.
b. To identify approaches/analytical techniques for determining the economicfeasibility of stress grading, and
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c. To examine the potential economic benefits and costs associated with, stress grading.
Study 4 Market assessment and strategies for the implementation ofstress grading rules for tropical timber.
This study attempted to assess, in the local perspective, the marketpotential of stress-graded timber for construction purposes. In particular, thecomponent attempted to
a. Describe the magnitude of potential unloading points forthe gradedproducts as well as the business appeal in producing them.
b. Conceptualize promotional approaches that could lead to the popularadoption of stress grading rules and ensure sale of graded timbers.
The study was conducted for 12 months. Initially, a lecture series withthe project staff as speakers was conducted to attune the members of theproject staff with the technical aspects of stress grading, the current use oflumber in construction, and the extent of implementation of local structuraland building codes and standards. As a result, conceptual frameworks of theeconomic, financial, and marketing studies were identified. Subsequently, aworkshop was conducted for the preparation of two sets of questionnaires,i. e. , one for producers and traders and another set for consumers and end-
The questionnaire for producers covered a. awareness andusers,
implementation, product procurement system and c. comments. That forconsumers and producers covered a. utilization of lumber in construction, b.awareness on lumber stress grading, c. implementation, and d. comments.(SeeAppendicesland2). ' '
Data were gathered for approximately eight months. Both primary andsecondary data were used in the analysis and discussions. Aside from thequestionnaires, primary data were obtained through pre-arranged meetings,interviews, and written communications with pertinent key persons in thegovernment and private sectors, as well as, international experts. Visits tosaw mills were also conducted. Follow-up interviews of respondents wereconducted whenever possible. This facilitated clarifications and immediatecollection of the questionnaires. An information brochure (Appendix 3) writtenin the local conversational language was prepared to gauge their approvaland solicit their comments on the implementation of lumber stress gradin inthe Philippines. This was made available to the respondents after their levelof awareness of lumber stress grading were tested.
International experts on lumber stress grading and non-destructiveevaluation were consulted throughout the pre-project study. Information onstress grading machines was obtained from overseas manufacturers who alsofurnished videotapes of actual stress grading operations in overseas mills.Secondary data were obtained from published articles in various journals,technical papers presented during FPRDl-Industry dialogues, the PhilippineForestry statistics, the Philippine Master Plan for Forestry Development, andcurrent newspaper articles on construction.
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Preliminary reports summarizing the results and implications of initialdata gathered were presented by the project staff in a consultative worksho(see program in Appendix 4) held at the end of tenth month of the study. Thepurpose of the consultative workshop was to validate and supplement resultsthat were gathered so far. The following key persons (see photo in Appendix5) representing the various sectors participated in the consultations.
I. Association of Structural Engineers of thePhilippines (AsEP)NationalstructuralCode of the
Philir)pines
2. Wood Science and TechnologyDepartment, University of the PhilippinesACademe
3. Provident Tree Farms, Inc. (PTF)Producer and member, Philir)pine WoodProducts Associatibn (PWPA)
4. Maple Resources DevelopmentTraded'producer and member, PWPA
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5. PANELCORP
Private Construction Sector, Trader
Dr. Joaquin O. SiopongcoMember, Committee on Wood
6. Department of Public Works andHighways (DPWH)Construction Sector, GovernmentImplementor, NationalstructuralCode
7. Task Force on Housing Technologies andProject Development, National HousingAuthority (NHA)Housing constructibn, Government Sector
8. Subdivision and Housing DevelopersAssociation (SHDA)End-user, Private Construction Sector
Dr. Virgilio A. FernandezProfessor and former Head of Department
Mr. MeIchor AbordeLumber Specialist
Mr. Freddie UyProduction Specialist
Engr. Lemuel S. MalicayVice President for Engineering andConstruction
9. Committee on Accreditation of InnovativeTechnologies, Housing and UrbanDevelopment Coordinating CouncilHousing technologies, GovernmentSector
Engr Judith SeseChief, Research and DevelopmentBureau of Research Standards
10 Ecosystems Research and DevelopmentBureau (ERDB)
Environmental Concerns, GovernmentSector
Architect Carmen TychuacoProjects Manage
11. Forest Management Bureau,Department of Environment and NaturalResources (FMB, DENR)Forestry Laws and Policies
Mr. Saritiago F. DucayExecutive Director
Dr. Edilbert RainirezDirector
For. Celso P. DiazDirector
For. Esther CadizChief, National Forest Division
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12. Forest Products Research andDevelopment Institute, Department ofScience and Technology (FPRDl-DOSTResearch
The workshop concluded with the participants' and project staffscommitment as members of the First Working Group on Lumber StressGrading in the Philippines. The support of the various sectors represented bthese organizations is expected in future undertakings towards thedevelopment and implementation of an appropriate lumber stress gradingsystem in the Philippines. The discussions which transpired in the workshowere incorporated in this report.
1.3 OVERVIEWOFTHE PRE-PROJECT REPORT
This chapter presented a rationale and brief background of the pre-project study.
Chapter 2 presents a literature review focusing on the technicalaspects, international research and development of lumber stress gradingmethods, as well as in the Philippines. Implications of such developments onthe potential of developing a stress grading method for the Philippines isdiscussed
Chapter 3 focuses on the current supply of and demand for lumber ofthe construction industry and projections for the period 2000-2015. Theseprojections, coupled with the type and quality of lumber currently available inthe market, were analyzed' as to their implications on lumber stress grading.
Chapter 4 discussed an analytical framework for determinin thefeasibility of stress grading lumber in the Philippines was explored. Thecurrent pricing and marketing systems of lumber are presented. The potentialeconomic benefits and costs associated with stress grading were describedand preliminary cost and return estimates were made.
Chapter 5 explored the market potential of stress-graded lumber in thePhilippines. This focused on the level of awareness, current market forstructural lumber, the market potential of stress-graded lumber, and themarket entry points and strategies for implementing stress grading rules in thePhilippines.
Chapter 6 summarizes the conclusions deduced from the fourcomponents. Recommendations for the immediate development andimplementation of lumber stress grading in the Philippines are presented.
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Dr. Emmanuel D. BelloDirector
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Chapter 2,
TECHNICAL REVIEWOFLUMBERSTRESS GRADING SYSTEMS
2.1 INTRODUCTION
Reliability in the structural design of timber structures requires the useof quality assured lumber. While there are countries which already maintain ahigh level of quality in engineered and semi-engineered timber structuresthrough the use of stress graded lumber, some lesser developed onescontinue to use and marketlumber as a traditional material, often disregardingits structural value.
The standards on Structural Classes of Timber and Stress Grading bythe International Standards Organizing Committee ISO/TC 165 is currentlybeing prepared. It is expected that each region, country or industry sectorwould write its own standard that should comply with the requirements statedin these ISO standards. These standards are intended to be normative,describing the essential features of all grading machine operations whererequirements have been kept to the essential minimum. Developing countriessuch as the Philippines can now devise stress grading systems with featuresthat are specific to their own production, technology infrastructure and marketconditions. The ISO standards on Structural Class requirements for StructuralLumber (second draft as of August 1998) and Stress Grading (Second draftsas of September 1997) cover grading of alltypes of species of timber andgrading by any type of grading machine.
The Philippines is currently experiencing a housing construction boomand it is projected that this will continue for at least the next 15 years'Concomitant to the inflow of industrialized construction methods andtechnologies is the growing demand for quality assured lumber. Lightframeand panelized construction methods using modular components with lumberstiffeners/frames have been introduced. Quality-assured lumber can be madeavailable for these and other construction applications if an appropriate stressgrading system is implemented. It is expected that volume of species and/orthe species mix, as well as, access to finance and technology will dictate thelumber grading system.
This technical review is prepared to provide a rational basis fordeveloping a suitable lumber grading scheme for the Philippines. Current
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developments must be assessed in order to identify the needs and direction offuture activities.
2.2
Engineered and semi-engineered structures demand materials ofspecific structural performance. To take advantage of this demand, timbermust compete effectiveIy with other structural materials such as metals,plastics, concrete and ceramics. Unlike these alternative materials, wood isheterogeneous and anisotropic. Its strength varies within the same tree,
STRENGTH GROUPING
between trees of the same species, and between trees of different species.Hence, the utilization of multiple species leads to difficulties in structuralassessments and consequently, so does marketing of both timber andfasteners. These difficulties can be overcome through strength grouping ofspecies and stress grading systems
Strength grouping is defined as sorting into strength groups in whichspecies having similar strengths are grouped together. Stress grading, on theother hand, is the expedient way of classifying and/or sorting sawn timberaccording to grades based on their predicted strength. Pre-determined stressgrades are suitably spaced at graduated intervals.
Strength grouping introduces the following benefits forthe country:o Each member species within the group can substitute forthe other, thus
solving the problem of supply.
* The traditional bias againstlesser-known species (LKS) can be overcomewhen these are grouped together with the premium and more commonlyused species, thus the entry of LKS onto the marketis facilitated.
* Grouping species with similar strength simplifies design and specificationprocedures.
o Formulation of comprehensive building codes for engineered structuresusing solid wood is facilitated.
o Technology transfer, in the form of design codes and manuals, isfacilitated.
* Marketing of structural timber is facilitated when pricing is based onstructural properties, not on species
* Internationally, countries can benefit from the use of internationallyaccepted methods of strength grouping through the interchange ofsoftwares, engineering design codes and manuals on framing sizes fordomestic construction.
2.3 STRESSGRADINGMETHODS
Stress grading is the act of sorting lumber into groups, each grouphaving a set of specified structural design properties which may convenientlybe subdivided into strength and stiffness types (Leicester 1981, Walker 1993).Rather than assigning design properties to individual pieces of lumber, stress..
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grading defines properties of allumber contained within a specific stressgrade.
Fig. 2 shows the basic elements of grading, namely the parentpopulation, evaluation tests, and the grading operation. The population maybe an identified species, a mixture of three to six species, or a mixture ofmany unidentified species. Evaluation tests may be the measurement ofdefects, density, bending and compression strength, bending strength andstiffness, or bending strength, tension strength and stiffness.
The efficiency of a grading system increases with the quantity and thequality of the information obtained in evaluation tests (Leicester 1984). Thegrade verification process or "in-grade testing" is time consuming andexpensive and hence not always performed. The grading operation is basedon a correlation that exists between the structural property of interest and agrading parameter.
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PARENT
POPULATION
EVALUATION
TESTS
Grading can be performed for a single species or a mixture of species.In the process of grading, a limit is placed on the acceptable range of agrading parameter G, or Gin which is in some way related to the structuralproperty of interest R* or Rin (Fig. 3). For example, modulus of elasticity (E) isused as a parameter to grade according to bending strength (Leicester1984).
Stress grading systems offers the following benefits:
* Pressure is relieved on well known, over exploited species through theincreased use of substitute LKS for construction applications.
* Timber producers can improve their profits by systematic pricing based onstrength of graded materials, thus reducing material waste, instead ofpricing their products uniformly regardless of strength.
* Engineers, builders, as well as building component fabricators will be ableto design and manufacture structural components and systems with just
Figure 2
----~------_____I
GRADING
OPER"ATION
The basic elements of grading (Leicester 1981)
Grade I
Grade 2
Grade 3
GRADE
VERIFICATIONI. ........
10
.
the right amount of material required for strength and stiffness. Users will-become more confident because the graded products they buy willperform in service as required and expected.
o- Stress grading would mean efficient utilization of sawn timber whichultimately leads to a wise conservation of our forest for sustainable yield.
CZ
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Figure 3
species
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GRADING PARAMETER, G
Ibl Mixture of Species
Schematic illustration of the sorting process for single speciesand mixed species (Leicester 1984)
2.3. , Visual Stress Grading (VsG) Method
Mechanical(or strength) properties of wood are determined by testingunseasoned (green) small clear, straight-grain specimens in the laboratory. Anormal distribution is then fit to these data and the 5'' percentile or "5 percent
I I
stress gradedpopulation fromo porticulurspecies
11
,
exclusion limit"is calculated. Allowable stresses (or working/design stresses)which are used to calculate the required dimensions of structural membersare evolved for a particular species taking into considerations factors affectinstrength. Such factors are strength variability of the species, load duration,and factors of safety as for accidental overloading, and error in desi nassumption and construction. The resulting figure after adjustments are madeis called the "basic stress" of green defect-free timber. Properties derived bthe clear wood procedure can be calibrated forthe size effect with antici atedresults obtained from tests of full-size lumber.
The oldest form of sorting lumber is visual grading. Considerin thattimber is never free from defect, it is logical to further apply strength reductionfactors to the basic stresses of defect-free timber. Visual gradin isconducted by inspecting all sides of the timber, taking note of the kind, size,number and position of strength reducing defects. Superticial defects may bein the form of knots, wane, decay, slope of grain, and defects caused bdrying such as checks, splits, warping, twisting and shaking. The gradinrules are drawn to discriminate between grades, so that the defects which areadmissible are those that do not reduce the strength of the timber below thegrade stress allocated for that grade. Most grading rules are based onstudies on "strength ratio" concept, the ratio of the strength of wood withdefects to that of clear wood.
Separate visual grading rules are supplied fortropical hardwoods andconifers, the main distinction being the treatment of knots. The knot-area ratio(KAR) method of assessing the influence of knots was introduced in the
,
,
United Kingdom and some European countries (TRADA 1974) for softwoodsbut this is comparatively complex as opposed to surface measurementapproach which is applicable to tropical hardwoods. The rules for tropicaltimber hardwoods are significantly simpler because of the limited occurrenceof knots in trees from natural forests. On the other hand interlocked grain is aproblem in tropical hardwoods which is often confused with slope of grain(UNIDO and TRADA 1984).
UNIDO has proposed model grading rules fortropical hardwoods as aresult of the Experts Group Meeting on Timber Stress Grading and Stren thGrouping (UNIDO and TRADA 1984). The hardwood rules (See Appendix 4)were based on TRADA's previous experience in other UNIDO projects, theirknowledge of stress grading rules in Malaysia, and their production of a draft,later on adopted by BSI in BS 5756, for tropical hardwoods graded in theUnited Kingdom. The visual grading rules summarize permissible limits of theoccurrence of defects in and grade ratios for Structural Grades I and 2(Appendix 5). The defects include slope of grain, knots, fissures, distortionsuch as bow spring and twist, insect holes, wane
In general, visual grading rules are subjective and complicated. Visualstress grading procedures may not be sufficient or particularly efficient.Madsen (1975, 1978, 1984a) pointed out that the failure mechanismsbetween clear and defective timber are different, hence, these should betreated as two different materials from the structural point of view. Visually
.
12
graded timber could be unduly conservative and could lead to inefficient usof. timber. Other disadvantages of visual grading systems are:
. It requires a cadre of trained or skilled graders familiar with gradingrules;
. factors that cannot be seen like internal defects and densit areimpossible to evaluate;
. visual grading is a slow process.
2.3.2 Mechanical Stress Grading (MSG) Method2.3.2.1 Bending Type Nori Destructive Testing/Evaluation
(NDT/NDE) machines
Stress grading of wood may be made alternatively by machines whichevaluate timber non-destructiveIy. This is known as non-destructiveevaluation (NDE) or non-destructive testing (NDT). Lumber graded bymachines is often called machine stress rated (MsR)lumber.
A machine stress grading (MSG) system has three essential factors; I)estimation of strength and sorting into classes or strength groups usin NDT,2) assignment of stresses, and (3) quality control to assure reliability(Bendtsen and Youngs 1981).
The oldest type of stress grading machine is the bending type and isthe most common type used today. Machines of this type rate the stren th ofwood on the basis that the modulus of rupture (R) and modulus of elasticity(E) in bending are highly correlated. The use of the correlation of R and E ofstructural timber as a basis for MSG has been proven beyond doubt to be amore efficient basis for stress grading than the inverse correlation of knot sizewith timber size; however, the measurement of edge knots in addition to thecorrelation of E and other strength-related properties can improve theefficiency of MSGs (BOStrom 1994).
In the linear regression of R and E, the lower confidence line of thedata is used as the predictor model to account for vanability in therelationship. Using Eater lumber is sorted into grades or E classes, and theallowable bending stress is estimated using the E Allowable stresses incompression and tension are assigned based on the relationship of theseproperties with bending strength.
The accuracy, reliability and efficiency of MSG systems are influencedby several factors that are inherent to the type of stress-gradin machine.Each stress-grading machine has its own relative merits under variousconditions. Frequent and regular control of stress grading machines has to beperformed. Two distinct control methods, namely, the output controlled andthe machine-controlled system, have been developed. The output-controlledsystem was developed in North America and controlis based on fre uentdestructive testing of samples of the machine-graded lumber. In the machinecontrolled system, assessment and control of the stress grading machine, as
,
,
13
well as, research efforts to this end, are constantly performed (Eurofortech1995).
In general, MSG machines feed the lumber longitudinalIy throu h aseries of rollers which hydraulically or mechanicalIy apply either a constantdeflection or a constant load and measure the corresponding load ordeflection. Lumber is often loaded in MSG machines in the flabNise OSitionbecause deflections are more measureble even at low stress levels, incontrast to the small deflections in the edgewise position which requires amore sensitive sensors. The flatwise position also allows flexibilit inadjusting to different widths.
Several prototype grading machines operate on the load or deflectionapplication/measurement principle. Examples of the first generation protoypeMSG machines are the Continuous Lumber Tester (CLT-I) (Fig 4) and theStress-0-Matic Machine (SoM)(Fig 5) in the United States and Canada, theMicrostress Grading and Piessey Computermatic machine in Australia (Figs 6and 7). Some second generation MSG machines are the TRU TimberGrader, and TRIMAG stress grading machines in South Africa (Fig 8), and theCookBolinderSG-AF(Fig9). '
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Figure 4 A diagrammatic representation of the CLT-, stress gradinmachine (Muller 1966)
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Figure 5 A diagrammatic representation of the Stress-0-Matic (SoM)grading machine (Muller 1966)
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A diagrammatic representation of themachine (Muller 1966)
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Figure 2.2 Principle design of the Computermatic ,ladin machine.
Figure 7 The principle design of the Computermatic gradin machine(BOStrom 1994)
Microstress grading
+^ Timber
15
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Figure 8 The TRIMAG mechanical1985)
10. EL. 1,010R WITH ELMAG BRAKE
11. MODULATED LZcirr TRANSMITrER
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13. MODULATED Llcirr TRANSCEIVER
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16. PILOT LIGHTS-LOCAL GRADE
17. PILOT Lickrs-FINAL GRADE
Pressroller
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Figure 9 The principle of the Cook Bolinder(BOStrom 1994)
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16
Except for the TRU Timber Grader, these machines are ca able ofprocessing 150 - 300 in of lumber per minute. Vibration and swinging of thetimber increase with increasing speed and this can lead to an underestimationof the timber stiffness. Some of these machines, such as the PIesseComputermatic, which make static measurements of E are ex ensive,however, they are capable of high throughputs rates. Others, such as theTRU Timber Grader are low-cost and have low through at which can kspot measurements of E.
With the condition that the stress grading machine is re ularlmonitored and accurately controlled, MSG is more objective and efficientthanVsG because it can rate irrespective of defects, species or specific ravit ofwood. It does riot discriminate commercially or non-commercialI woodspecies contributing to better or maximum utilization. One advantage of MSGis that fewer grades are required since all species can be graded in a limitednumber of stress settings. For example, in the United States, there are over80 different design values for a 100 x 50mm visually raded softwoodscompared to only 10 machine grades. This shows the obvious advanta e ofhaving reduced complexity for the designer and fewer inventory for thefabricator.
Although stress grading machines can account for some influences ofdefects on strength, an edge knot on a piece of lumber does riot influence Ewhen tested as a plank as the knot would ifthe piece was tested on the ed es(E of edge). The E value of the plank is indifferent to the location of suchknots. Hence, visual restrictions are necessarily needed to jin rove theefficiency of machine stress grading systems (Bendtsen and Youngs 1981,Us DC 1990). A similar effect is also true with the slope of grain of lumber:Shear and compression perpendicular to the grain are likewise not stron Icorrelated to either E of edge or the E of plank and the grade values of thesestrength properties are independently determined by correlating with densit .Therefore, some visual overrides are needed to eliminate pieces havinunacceptable splits, wane and distortions.
2.3.2.2 Other Types of NDE Machines
Other types of machines base their rating on vibration, resonant ulsetechnique, X-rays, and capacitance devices to measure other strength-relatedproperties of lumber. Some machines incorporate both bending type and themeasurement of some other strength-related property. Some of them areinstalled directly in sawmills to determine the local slope of the rain aroundknots or determine the basic density of the wood which are prime variablesinfluencing strength. A limitation of density as a grading predictor is that it hascapability of predicting inherent wood strength only; it does not reflect thepresence of knots, cross grain, etc. Density may be adaptable as a lonepredictor of strength in species essentially free of knots and darna in SIo eof grain.
Asan example of an NDE machine, the Pilodyn measures relativedensity using the depth of penetration of a spring-loaded pin. Relative densitis the best single index of inherent wood strength for some properties and
17
species. It can explain as much as 909', of the variation of strength in clearwood. The device has been proven effective in measuring tensile and flexurelstrength of high-grade lumber but may not be effective for low-grade material.
High-speed non-contacting electronic graders, such as the Finnograder(Fig 10), simultaneously measures several lumber characteristics such asdensity, moisture content, knot size and location, and slope of grain, and,temperature. Measurements can be obtained for every 10 min and normalprocessing speed is 150-300 in/min. An advantage of the Finnograder is thatmeasurements start at about 50 mm from the leading end and stops at around50 min before the trailing end (BOStrom 1994). Density is measured usinggamma-rays, slope of grain- through polarized microwaves, knotmeasurements through microwave radiation.
The Sylvatest (Fig 11) estimates the grade of timber based on species,ultrasonic wave speed, shape of cross-section, moisture content andtemperature. It is a field instrument which consists of a transmitter probe, areceiver, another fortemperature measurements, and a computer.
A prototype commercial stress-grader with two sets of microwavescanners comprising of a knot detector and a slope-of-grain measurementunit has been reported (Leicester and Seath 1996). Milltrials indicated thatthe scanners were stable in operation and that adequate process controlprocedures are feasible. An increase of more than 5% recovery wasindicated by the data from one population of timber. Difficulty, however, lies inconstructing algorithms under conditions of changing resource.
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18
Transmitter
Figure 2.4 Principle of Sylva!est
Computer
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Figure 11 The principle of the Sylvatest(BOStrom 1994)
.
Specimen
2.3.3 Other Stress Evaluation Methods
Other engineering methods of evaluating the stress grades of timberinclude "proof loading" and "in-grade testing".
2.3.3.1 Proof Loading
Most stress grading machines are developed for single species in millswith large throughput. The proof grading system (Fig 12) was developed forapplication in a situation where there is little available capital and technologand is more appropriate for mills with low throughput and many species(Leicester 1985). This is done by quickly sorting a species or group ofspecies having similar strength into one or two grades. Then randomsampling and testing of strength are made for each batch to statisticalIyestablish an estimated variability factor for each of the respective lot. A proofload is determined for each lot so that 95% of the pieces of that particular lotwill not failif the load is applied. In other words, in the process of grading,pieces that break using the proof load are culled and the number should riotexceed 5% of the batch (Leicester 1988).
It is important to remember, however, that the system of grading islimited to grading just one untiltwo stress grades butthe system assures thateach piece will meet minimum strength requirements. Compared to machinestrength grading, proof loading is straightforward and in particular, requires noa prioridata aboutthe timber source to be graded. It has been pointed out,though, that one disadvantage of this system is a possibility of using damagedtimber as a result of the application of proof loading. However, this is riot
19
Receiver
..
entirely true because proof load factors contain an allowance forthe effects ofdamage. In other stress grading systems, low quality timber may besubjected to stress levels which are compareble to the proofloads. The otherdisadvantage is the under rating of stronger species mistakenly mixed withthe lot that is tested for its lower strength distribution.
timber input
.
group A
damagedtimber
rejected
PROOF
STRESSA
Figure 12. The schematic illustration of the proof grading procedure(Leicester 1985)
At the National Timber Research Institute (NTIR) in Pretoria, two proofloading machines were developed. Firstly, a high-speed proof loadingmachine for battens (nominal cross sectional dimensions: 38 x 38, 38 x 50, 50x 50) was designed based on the principle of the cantilever beam with aconcentrated load at the free end (Vinopa1 1985). Secondly, a laminatedbeam tester which is used to proofload finished laminated beams and gradesthem according to their strength based on deflection (Figure 13 and 14).
In Australia, most proof loading machines used in mills are of theHilleng brand continuous tester which is manufactured in Brisbane and cost $Us 15,000.00 in 1985. The proof stress used in Australia is bending althou ha tension stress would be equally suitable (Leicester 1985). The machineconsists of a steel frame with electrically driven pinch rollers for transportingtimber through the unit, and airoperated loading roller for applying a pre-setload to each stick. Throughput speed is from 20 to 60 in/minute.
ROUGHSORT
group B
grade Aoutputtimber
PROOFSTRESS
B
damagedtimber
rejected
grade Boutputtimber
20
, PROOF LOADING HACHI, !E FOR BATTENS
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7. LOAD AIR CYLINDen
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Figure 13 The NTIR high-speed proof loader for battens (Vinopa1,985)
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Figure 14 The NTIR proofloaderforlaminated beams (Vinopa1,985)
.
9. MODULATED Lickr
TRANSMZTTER
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11. DEFLEcrROHErER WITH
norARV ENCODER
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13. PrtOr Llcm
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21
2.3.3.2 In-Grade Testing
"In-grade testing"is the testing of samples from a particular species (orgroup of species with similar strength), size and grade of full-size structuraltimber. The samples are selected at random from sawmill, facto orlumberyard then tested for strength and stiffness in bending. The purpose ofin grade testing is to establish design stresses for use in quality control so thata minimum strength property is met. This system is different from proofloading system because proof loading determines the amount of load incontrolling the strength quality of wood. Different testing configurations for in-grade testing are used all over the world but there are methods forequivalencing the various procedures (Leicester at a1. 1996a). A comparisonof in-grade testing procedures of Europe, North America and Australia/NewZealand showed that the European procedure can underestimate the in-service bending strength and stiffness and slightly overestimate the in-servicetension strength (Leicester et. a1. 1996b). Differences in testing proceduresare more than academic significance because these can lead to technicalbarriers in the international trade of structural products.
2.4 DEVELOPMENTAND IMPLEMENTATION OFLUMBERSTRESSGRADING IN VARIOUS COUNTRIES
Th advantages of strength grouping can not be more emphasized intropical countries where there are thousands of species. Australia was first torecognize the advantage of strength grouping their enormous number ofindigenous species for structural purposes (Leicester 1948). The StandardsAssociation of Australia and the Standards Association of New Zealand havejointly published standards on in-grade and stiffness evaluation of stress-graded timber, as well as, procedures for monitoring structural properties.
The Australian Standard (SAA 1986b) offers two procedures forclassifying timber into a particular strength group. The first is, whereadequate but limited data of mean strength characteristics are available, apositive strength grouping is possible. The alternative way is when data arenot available, the mean airdry density of the timber can be used instead.
Application of visual stress grading rules was reconciled andrationalized with strength grouping which resulted into only 12 interlockinstress grades instead of 2500 individual stress grades for Australian s ecies(SAA 1986a).
As/NZS 4490 (1997) covers procedures for monitoring structuralproperties for stress graded timber and it is used in achieving reliablestructural quality in stress-graded timber. In Australia and New Zealand,monitoring is a continuous program carried out on a daily, shift or batch basis,and is regarded as essential to the establishment of reliable structural qualit .The procedure includes determining strength and stiffness values andmonitoring of resource and stress-grading operations.
The ASEAN region being located in the tropics by nature has a Iar enumber of different species of woods. For efficient utilization, each counthas its own system of classifying theirtimberfor construction purposes.
,
,
,
22
In Malaysia, there are more than 3000 species which belong to 90families and most of these are hardwoods (Tahir et. a1. 1996). Out of these,177 species, classified under 56 groups of commercial species, have beenclassified in 4 strength groups (A, B, C and D) in the order of decreasingcompressive strength (Burgess 1956). Basic and grade stresses for thestrength groups are formulated from the weakest species in the grou(Rahman 1971). Some species which have not yet been tested were alsoincluded in the groups. The system was modified and updated in 1972(Rahman 1972).
There are two types of grading practiced in Malaysia, namely "quality"grading and stress grading (Tahir 1996). Quality grading is based on theexternal appearance of the lumber whereas visual grading, based on strengthgroups, is conducted in accordance with the Malaysian Grading Rules (MTIB1989). Their system classifies timber as "Select Structural", "StandardStructural" or "Common Building". Currently, even if stress graded material issecified, th k "specified, there is no market support to provide the desired material.
A Computermatic MK2 stress grading machine was delivered to FRIMin inid 1981 by Metriguard of Washington, USA. The equipment is based onthe NDE of MOE of timber measured by vibration. FRIM is stillin the sta e ofcalibrating the equipment for Malaysian hardwood species (Khaidzir 1998).Despite work on the MK2, it is believed that popularization of stress radedtimbers may lie in the development of other reliable but simpler methods ofgrading. Other methods being explored are nondestructive testing by stresswave and indentation methods. Proof grading is perceived to be a o0dmethod to eliminate weak pieces often containing brittleheart, which isundetectable by other methods.
The Indonesians base their strength grouping from the specific gravitof wood with various strength relationships (FPRl of Indonesia 1974).Arbitrary specific gravity values were chosen for five groups and therespective strength values were calculated from specific gravity-strength valuerelationships. This method was introduced by Burger(1923) who selected 50Indonesian hardwood species and under dry condition, studied therelationships between specific gravity and various strength components.
In 1987, Sudokusumo has developed a machine, called "PANTER" orplank sorter, for stress grading structural timber. Based on deflectionmeasurements and correlation between E and R, the device has been usedon-site to grade timbers for selective government construction projects.However, the concept of stress-graded timber is generally unknown atsawmills and timber sales outlets. For construction, most timber is purchasedon the basis of experience.
Karnasudirdja (1979) has introduced a technical way of coinputatingallowable stresses for strength classes based on density. Lack of technicalsupport, including strength data and system of information dissemination hasseverely limited the implementation of a stress class system into theIndonesian market.
.
,.
23
Thaitimbers are divided into three groups based on stren th anddurability (Son0 1974). They are grouped as: I) "hardwood" species, thosewith MOR of more than 1000 kg/cm' and durability of more than 6 years, 2);"medium hardwoods", 600-1000 kg/cm' MOR, 2-6 years durability; and 3)"softwoods"less than 600 kg/cm' MOR, less than 2 years durabilit . Lessdurable timbers can be upgraded, however, provided that proper treatmentwith wood preservatives is made.
In the United States and Canada, MsR lumber is also sub'eated tovisual override because the size of edge knots in combination to E is a betterpredictor of strength rather than using E alone (Bendsten and Youngs 1981).Other visual restrictions are based on checks, shakes, splits, wane and wThe American Lumber Standards Committee (ALSC) has standards for visualgrading and machine grading system. Machine graded lumber does not carthe same grade designations as visually graded lumber. The National Desi nSpecification for Wood Construction lists two broad classes of mach'graded lumber: machine stress-rated lumber (MsR) and machine-evaluatedlumber (MEL). The MsR graded are designated numerically by their designbending stress and modulus of elasticity or stiffness values. The MEL radedare designated by the letter M followed by a number which does riot directlcorrespond to a design property (Groinala 1996).
MsR lumber has gained acceptance for highly engineered a Iicationssuch as laminating stock and floor and rooftrusses where better ualit andreliability are obvious advantages. Reliability-based designs is receivinmuch attention and this will promote MsR. The existence of a coin etitivevisual grading system proven through the decades of successful experience,has been a majorinhibitorin the wide acceptance of MsR. Even thou h MsRis more easily adapted to automated production lines, it is also more costlthan visually graded lumber, at least in the United States.
Canadian machine stress rated (MsR) lumber is graded to theStandard Grading rules for Canadian Lumber published b the NationalGrades Authority. In a typical MsR machine used in Canada, forces areapplied on both sides of the lumber, on flat, with deflection measured eve150 min along the length of each piece. Stiffness is measured and recordedby a small computer, and strength is assessed by correlation methods.Lumber is processed and marked with grade marks at a speed of 365 in erminute. MsR requires visual monitoring to improve the correlation betweenmachine assessment (on the flat) and performance on edge as in a joist.Visual grading is employed to monitor characteristics that cannot be assessedby existing machines, such as wane, warp, checks and inariufacturinimperlections (MHBH 1981).
In the tropical timber producing region of South Africa, timber is notstress graded. In the 1960s, suitability of stress grading machines such asthe Mark I Micro-stress Grader have been looked into and recommendationswere for the South African Bureau of Standards to set the machine inmotion for the control of this stress grading method. Today, there are nocodes of practice for timber construction. Timber is generally not used in
24
.
construction because timber is very expensive. This is because the ex ortmarket dictates the prices forthis material- even those for local consum tion.Few technical data are available for establishing design stresses. Assistancein developing standards, establishing grading rules, and implementing theseprocedures would be necessary to promote the use of stress graded timber.
Structural hardwoods in the United Kingdom are strength raded inaccordance with BS 5756 (1997) on specification for visual grading ofhardwood and are allocated in strength classes defined in BS EN 338 (1995)on strength classes of structural timber.
The hardwoods strength graded to BS 5756 and assigned to BS EN338 which includes six strength classes (030, 035, 040, 050, 060 and 070)are Baiau, Ekki, Greenheart, Iroko, Jarrah, Kapur, Karri, kernpas, Keruin ,Merbau, Oak, Opepe amd Teak. With the exception of Oak, all of thesehardwoods belong to the strength grade HS (TRADA 1997a).
Aside from visual grading, machine stress grading is also undertaken inEurope. BS EN 519 recognizes the two systems of machine gradin that arealready accepted in the United Kingdom; machine controlled and out atcontrolled (TRADA 1997b). Lumber is machine graded to BS EN 338.Lumber that is machine graded to the North American rules is acce ted in theUnited Kingdom.
Structural timber design in the United Kingdom is generally carried outto BS 5268 The Structural use of timber Part 2 (1996) Permissible stressdesign, materials and workmanship of both temperate and tropical origin. Thecode defines three service classes:
Service Class I - characterized by a moisture content in the materialscorresponding to a temperature of 20' C and the relative humidity ofthe surrounding air only exceeding 65% for a few weeks each year. Insuch conditions most timber will attain an average moisture content riotexceeding 12%.
Service Class 2 - characterized by a moisture content in the materialscorresponding to a temperature of 20' C and the relative humidity ofthe surrounding air only exceeding 85% for a few weeks each year. Insuch conditions most timber will attain an average moisture content notexceeding 20%.
Service Class3 - due to climatic conditions is characterized by hi hermoisture contents than Service Class 2.
Strength classes give values for strength and stiffness properties anddensity, these values derived from test values and do not take into accountfactors of safety and other factors included in the design process. Stren thclasses offer a number of advantages both to the designer and the supplier oftimber. The designer can undertake his designs withoutthe need to check onthe availability and price of a large number of species and grades. On the
,
25
other hand, suppliers can supply any of the species/grade combinations whichmeetthe strength class callfor in a specification. The strength class systemallows a new species to be introduced onto the market without affectinexisting specifications.
BS EN 338 gives characteristic values for strength and stiffnessproperties for each strength class. These are used in'the limit state desi nsystem laid down in the Eurocode 5 and are derived directly from test values,taking no account of factors of safety or other significant factors which areapplied as part of the design process. It is noteworthy that the original ISOdraft standard on Structural Classes was based on EN338 and EN384, onmachine graded lumber based on EN 519, and that on visually graded lumberbased on BS 4978.
2.5 DEVELOPMENT OF LUMBER STRESS GRADING IN THEPHILIPPINES
In the Philippines, a rationalization in the utilization of wood was made(FORPRIDECOM 1980) in order to improve the supply situation and makeavailable many timber species for their best end-uses. Some end-uses thatwere considered were: poles and piles, veneer, ' pulpwood, heavy and lightconstruction, furniture and cabinets, millworks/joinery, woodcrafts andnovelties, packaging, tool handles, sporting goods, and musical instruments.In finding a suitable wood species for a specific end~use, wood propertiessuch as dimensional stability, strength, natural durability, permeabilit ,machinability, surface finishing and growth characteristics are the criteriaconsidered.
The system of classifying wood categorizes properties in A (good), B(medium) and C (bad). For instance, where strength and specific gravity areconcerned, the property values which are deemed essential for a particularend-use are categorized as "A"in recognition of the fact that different end~users have different requirements in so far as strength and density areconcerned. End-use properties criteria for house framing, for example, areMOR, durability (DUR), treatability (TRT), shrinkage (SHR), specific gravity(SPG), workability (WRK), and seasoning (SEA). In selecting the properspecies, wood species with at least 2 "As" and no "C"in MOR, DUR/TRT/SHR and SPG belong to Grade I. Species with alleast"B"in MOR and I "C"in DUR/TRT, SHR and SPG belong to Grade 11, while species fallin belowGrade 11 are classified as Grade 1/1.
The visual stress grading system shown in Appendix 8 was introducedin the Philippines in 1970 by Lauricio et. al. and the rules were adopted b theAssociation of Structural Engineers of the Philippines (AsEP) in the NationalStructural Code of the Philippines (NSCP 1972). Recommended workingstresses for visually stress graded timber derived earlier by ESPiloy (1981)and updated by Siopongco and Rocafort in 1992 are listed in the NSCP(Appendix 9). The NSCP now includes the grading rules and allowablestresses for coconuttimber obtained from the study made by ESPiloy (1988).
26
The Philippines has also developed a strength grouping s sternsummarized in Appendix 10 (ESPiloy 1977). In order to simplify various listsof stresses for the various structural species, the system consisting of fivestrength groups was based on MOR related with other strength properties.The progression of 1.25 spacing between strength limits of MOR was decidedin such a way as to provide economical design, but should not be so narrow-a-spacing that it will be impractical from the standpoint of inariufacturin ,grading, stocking and other requirements. A narrower range per group in thesystem tends to separate species apparently belonging to the same group. Awider spacing, on the other hand, will make stronger species in that rousuffer a decrease in stresses and can lead to over-designed structures.
Furthermore, a set of working stresses for each strength group wasevolved to simplify the voluminous design information for structural Philip inetimber species (ESPiloy 1984). As of 1995, the strength properties andcorresponding strength grouping of 121 commercial, 45 lessenknown and 21plantation timber species have been published (Tamolang et. a1. 1995).These species have been classified into five strength groups with theirrecommended end-uses (see Appendix 11). The strength values provide abasis for deriving allowable working stresses for Philippine timber used forstructural purposes.
In the process of deriving the basic working stresses, each stren thgroup was treated as a hypothetical species and several strength reducingfactors were applied to each of the strength group limits similar to what havebeen done on deriving basic stresses of individual species (ESPiloy 1976a,1976b, 1978). ,
Table 2 shows the basic working stresses forthe major design stren thproperties for the five strength groups of timber. The stresses indicated intheir corresponding groups are equivalent to 80% of the strength of cleartimber using the grading rules in Table 2. Stresses found one stedownwards relative to theirrespective groups indicate a 649', grade while 509"grade stresses are found 2 steps downwards. Figures that are one steupwards relative to their corresponding groups indicate the stresses of defect-free (100% grade) timber. Note that the table also shows the stresses oftimber at 16% moisture content. The advantage of using such techni ues isits simplicity whereby only 8 sets of stress grades based on 5 strength groupsand 4 stress grades.
Despite the incorporation of strength groups and stress grades in thestructural code, no stress graded lumber is available in the market nor is thelumber sorting process in the mills (see Section 1.1 in Chapter I) tied up tosuch strength groups. Civil/structural engineers refer to the NSCP forstrength grade design values in their calculations for required sizes of lumber,and submit these to Building Officials as part of the buildin ermitrequirements; however, these are practically disregarded during construction.Building officials are not bent on monitoring whether the specified species andstrength of timber were installed as they have no way of determining this.Constructors would be concerned with the size and species of lumber that isspecified in the plans, however if the species is riot available, size becomes
27
the only consideration and grade is disregarded. Prices of lumber are alsoriot structured with any reference to strength groups or stress grades (seeSection 4.3. I in Chapter 4) and constructors would opt for readily availableand equally priced imported lumber with unknown strength if the premiumspecies indicated in plans is riot available.
Table 2 Basic working stressed for grouped Philippine structural timberspecies
STRENGTH CLASS
GREEN
.
SEASONED*
Ci
C2
STRESSDESIGNATION**
C3
CD2
C4
CD3
C5
CD4
25
CD5
BENDINGAND
TENSION
S20
*
Refers to timber materials with moisture content of 16% and below**stress designation is based on the basic working stresses for bending
SI6
TYPE OF STRESS (MPa)
SI3
COMPRESSIONPARALLELTO
THE GRAIN
25.9
SIO
As presented in Chapter 3, the present supply of lumber in thePhilii fi 'Philippines comprises of lessenknown or lessenused species (LKS/LUS)coupled with the introduction and influx of imported mixed timbers whoseidentities and properties are generally wanting. Additionally, timber harvestsfrom the emerging industrial tree plantations now form part of the total woodsupply. With this supply scenario, there is an apparent need for a speciesindependent grading system, i. e. , one that requires no prior knowledge ofspecies properties.
To date, no stress grading machine has been introduced in thePhilippines. The possibility of acquiring a Metriguard 7200 HCLT machine forresearch purposes was explored by the Structural Design and EngineeringSection of FPRDl and it was inquired that the machine would cost $119,415.00 excluding data system and spare sensors (MCTimpeny 1998).Learning from the Malaysian experience, expensive machines such as thisthird generation MSG is not practical forthe Philippine situation. Simpler, lessexpensive machines that operate on a species-independent principle is ideal.
20.5
S8
16.3
S6
13.0
17.3
SHEARPARALLEL
To THEGRAIN
S5
10.3
13.3
8.18
10.6
6.49
MODULUSOF
ELASTICITY
(E)3.07
8.18
5.16
6.31
2.37
5.01
1.88
20500
3.87
1.45
16000
3.07
1.15
12200
0.90
9200
0.71
7100
0.56
5500
4200
3200
28
In addressing the apparent need for a species independent gradinsystem and considering financial limitations, an exploratory concept has beeninvestigated by first utilizing a simple timber framed stress grading machine atthe FPRDl(See Fig 15). It had a cable, pulley and lever for convenience inloading (or unloading) a specified weight when flexing timber to be graded inthe flabNise or plank wise position (FPRDl and ITT0 1998). Deflectionreadings were made from a dial gauge located beneath the inid-span of thetimber. The system required that the cross section for each size of thematerial was made uniform preferably with a thickness tolerance of about :tjinm. Forthe width, a greater tolerance of about :t 3mm is permitted. Thestress of the graded piece was determined by the deflection criteria developedby actual experimentation. Most often however, dimensional variation in thecross section varied widely which cannot be avoided.
r
I
LEVER
MAIN, ;SUP, :^, RTFRAME,
.
.
FIGURE 15 Schematic diagram of simple stress grading machine atFPRDl used in initial investigations of the concept of speciesindependent stress grading machine
DEAD weldrr
DIAL GALi@^
MAGNETICSTAND
I"
.
..
29
Using the deflection criteria derived from a population of timber,prediction of actual strength of timber with this simple machine was 79%accurate. Improvements, such as the incorporation of electronic sensors,automatic data acquisition, processing and stress marking systems areneeded for the machine to operate at an acceptable rate and efficiency inproduction operations in the sawmill. Economic restraints do not allow for aslow deliberate process where loading of lumber into the machine, as well asapplication of load, and obtaining deflection readings are manually performed.Initialinuiri th t f"I " "Initial inquiries on the cost of "electro-mechanizing" the machine, integratingsaid improvements excluding the data acquisition hardware and software, andan automatic loading system, will cost about $2,500.00 (Mate0 1998).However, the reliability of the machine must first be verified before introducingfurther improvements to suit sawmill operations.
,
,.
2.6 IMPLICATIONS OF THE TECHNICAL REVIEWON THEOPPORTUNITIES OF LUMBER STRESS GRADING IN THEPHILIPPINES
Compared to its ASEAN neighbors, the Philippines is still at par as faras visual grading is concerned. The ASEAN systems of grading, especiallythat of Malaysia, seem universal in nature with slight variations in the gradingrules. The Philippines, however, enjoys a slight advantage over theMalaysian system in the sense that the Philippine system incorporates andties up strength grouping system with only three visual stress grades reducingthe number of grades significantly. This is possible because the spacing usedboth in strength grouping and stress grading was the same. Furthermore, thePhilippines has developed a scheme on how to selectthe best wood speciesfor particular end-use for improved utilization and marketing purposes. Visualgrading rules and grade stresses for coconuttimber used in construction havealso been prepared.
Compared to developed countries, the development of lumber stressgrading in the Philippines has been relatively slow. However, technical dataof its timber supply specially those for construction has been continuouslyupdated. Requirements for a stress grading system such as strength groups,strength classes based on end -use, visual grading rules, and strength gradeshave now been established in the National Structural Code of the Philippines.It has been established that machine stress grading can riot substitute visualstress grading, it is an adjunct (Mettem 1982). Combined visual andmechanical methods may well be the best choice of stress grading especiallin developing countries. Hence, the Philippines needs to identify a species-independent mechanical stress grading system. For greater benefits, thissystem should be tied up with the present strength grouping system whichhas reduced number of stress grades compared to other systems. MsRprediction models could be established by tests of lumber from initialshipments or shiploads of lumber. Quality controltests should be put in place
30
in order to establish whether the MsR prediction modelis appropriate forsubsequent shipments.
Before any grading machine can be used effectiveIy, grading criteriaare needed. Tests of full-size specimens from species that are actually usedfor construction will be conducted to establish the relationship between R andE. Since the E of the plank containing defects like edge knots, slope of rain,splits or some sort of distortions are not sensitive when graded with plankwise loading, corrections incorporating visual grading shall be made. Otherstrength properties such shear, compression parallel and perpendicular to thegrain are also insensitive to the E of the plank. Hence other means to relatetheir strength in the grade should be made. Additional tests must beconducted to determine these properties including their respective specificgravities. Test specimens should be taken from the same undamaged stickwhich have undergone stress grading.
Development of an appropriate machine will include but not limited tothe concept being investigated through the simple wood-framed stress-grading machine developed at FPRDl. Further studies to validate theprinciple involved and improve its efficiency should be conducted.Incorporation of electronic sensors, automatic data acquisition, processingand marking system using an "artificial intelligence software" isrecommended. The machine that is envisioned for use in local sawmills doesnot necessarily have to be so sophisticated and expensive as those usedtoday in developed nations. A developing country like the Philippines cannotafford to buy such machines because doing so would result to bigger ricedifferentials between graded and ungraded timber, which is opposed to theobjective of the study. Perhaps, such machines will be taken intoconsideration in the future when producers and consumers alike have alreadrealized the advantages and benefits of stress grading. Therefore, for thePhilippine condition, the ideal prime design considerations forthe machine aresimplicity, affordability and reliability so that those involved in the structuraltimber trade could easily afford to purchase or copy and fabricate one, Whilea mechanical stress grading machine is being developed, if only to emphasizethe value of quality assured lumber, the concept of proof testing can beintroduced in sawmills specially where lumber is processed for specificmarkets, i. e. , prefabricated components with specific loading requirements.
,:
,
,.
31
Chapter 3
DEMANDAND SUPPLYOFTROPICALTIMBERFORCONSTRUCTION PURPOSES IN THEPHILIPPINES:IMPLICATIONS FOR LUMBERSTRESS GRADING
I
"
3.1 INTRODUCTION
The tropical rainforest is characterized by the heterogeneit anddiverse composition of timber species. In the Philippines, more than 3,000timber species, inclusive of the premium and preferred species numberinabout 200 for various end uses, have been reported. However, the su I ofwell known and commercially important timber species has dwindledconsiderably due to over exploitation. Efforts have been made to develop andsearch for alternative sources of wood raw materials in more recent years, Asan offshoot, the wood industry sector has resorted to the processing andutilization of other wood species both from local and foreign sources.
Presently, a significant volume of the local wood supply available in themarket belongs to the so-called lessenknown or lessenused species(LKS/LUS) coupled with the introduction and influx of imported mixed timberswhose identities and properties are generally wanting. Additionally, timberharvests from the emerging industrial tree plantations now form part of thetotal wood supply.
With this prevailing situation, this project component was undertaken toassess the wood supply and demand situation in the Philippines. Specifically,the objectives were to: a) generate information on lumber supply and demandsituation in the Philippine construction (housing) industry; and by determinethejinlicationf I dd 'the implication of supply and demand trends on the prospects of stressgrading.
3.2 USESOFWOODINCONSTRUCTION
Lumber continues to be acceptable construction material in thean
Philippines today. Based the survey conducted among a group ofon
engineers and architects, 78 have used lumber in structural and9"o
architectural components in buildings, mostly residentials and small buildin s
32"
of up to two-storeys. The rest have used lumber in road and brid econstruction, mainly as scaffoldings 'and formworks. The respondents whoclaimed to have no projects where a significant volume of lumber was usedwere those who were employed in multi-national construction coin aniesimplementing big projects, those utilizing mainly steel and reinforced concretesuch in multi-storey commercial buildings and horizontal structures such asroads and bridges. Among those who have used lumber, 75% ex ressedtheir dissatisfaction of the quality of lumber delivered at the construction site,and about 699", indicated that the supplier was, however, willing to re lace lowquality pieces, i. e. , those with defects such as bows, wanes, twists, as well asundersized lumber. All of the respondents clamorfor quality assured lumber.
Considering the various types of vertical structures in the Philip ines,wood is widely accepted for structural components of houses and apartments,schools, and public utility buildings such as assembly halls and health centers(Sortan0 4986). In both rural and urban areas, wood is traditionally used forstructural and architectural purposes. It is often preferred by builders,craftsmen and home owners instead of concrete, metal or steel due to thefollowing advantages:
. Wood is available in a variety of colors, textures and grainconfigurations.
It can be machined with minimal consumption of energy, isworkable with glues, nails, and other forms of mechanical jointinand fixing medium.
It is relatively strong in relation to its weight and as a general rulesuitable for medium to heavy construction.
. It has good acoustical properties making it desirable for auditoriumsand theaters.
. Unlike metals, its source is renewable, is biodegradable, thusenvironmentally friendly.
Wood, as a construction material, has disadvantages as well. Themajor disadvantage, being a product of a biological process, is its variablemechanical strength in different directions, at times varying b a factor ofmore than 10:1 within the same tree (Leicester and Seath 1996). For wood tocompete with other construction materials, a sound knowledge of its stren thvanability is required and related studies should be conducted to counter itslimitations in utilization. The best quality pieces should be used with minimumwaste.
I.
.
.
3.3 PHILIPPINETIMBERSITUATION
Presently, the Philippine timber supply comes from thenatural second-growth forest, plantation forest, and imports.
.
remaining
33
3.3. , Natural(Residual or Second-Growth) Forest
As of 1996, the forest area of the- Philippines was placed at 5,493million (M) hectares (has) or 18.3% of its total land area of 30 M ha. Of thesetotal forest areas, 14.64% or 0,805 M has are old growth or vir in forestswhich have been placed under the National Integrated Protected AreasSystem (NIPAS) since 1992. The residual and pine forests available forcommercial exploitation comprise about 2,812 M has. (51,199'.) and 0.23 Mhas (4.1%), respectively. The total volume of timber in the remainincommercial forests (residual and pine forest areas) is estimated at 415,924 Mof which 391,915 M in' are in the dipterocarp residual areas and about 24.0 Min are in the dipterocarp pine forest (Table3).
Log production in the Philippines had a general downward trend. Forthe 10-year period (1987-, 996), log production decelerated from 4.15 M in' in1987 to 0.76 M in' in 1995. However, in 1996, there was a SIi ht increase involume of local log production at 0,771 M in' or nearly 2% overthe 1995 level(Table 4). The increase in log production from 1995 to 1996 may have beenattributed to the increase in share of the PLTPs which were mainlconcentrated in Mindanao provinces. It has doubled its share compared to its1995 contribution (14^^). TLA holders contributed the bulk with 41% share,IFMA with 34%, PTLA with 69',, PFDA with 2%, CFMA, I% and othert e oflicense, 2% (Table 5).
,
Table 3. Volume of Timber in Philippine Commercial Forests: 1996
FORESTTYPE
Dipterocarp, Residual
Common hardwoods
Furniture Wood
Softwood
Others
Dipterocarp, PineCommon hardwoods
Common Furniture Wood
Softwoods
Others
Source: 1996 Philippine Forestry Statistics, FMB-DENR.
VOLUME ('000 in3)
TOTAL
39, ,9.5
198,410
128,769
6,804
57,932
24,009
100
31
23,829
49
415,924
34
,
Table 4. Local Log Production ('000 in') Philippines, 1987-, 996Year
1987
1988
4989
1990
1991
1992
1993
1994
1995
1996
Total
4147
3809
3169
2503
1922
1438
1022
957
758
771
Sawlog/Pulpwood
,
341
3185
2796
2156
1561
800
685
805
589
400
AnnualAve
Growth,%/yr
Poles andPiles
Source : 1996 Philippine Forestry Statistics, FMB-DENR
681
615
351
335
349
487
241
149
167
365
2050
Table 5. Log Production by Type of Timber License, Philippines,1996
Veneer logs
16.53
TIMBER LICENSE
1669
54
9
22
12
12
151
96
3
2
6
19.32
IFMA
PTLA
PFDA
PTLP
CFMA
OTHERS
374
3.17
Source: 1996 Philippine Forestry Statistics, FMB-DENR
VOLUME (in')
Likewise positive growths were reported in 1996 over 1995 in lumber,veneer, and plywood production which registered 9% (313,000 in'), more than100% (82,000 in'), and 759", (508,000 in'), respectively, (Table 6).
The decrease in local wood supply from the natural forest is due to thefollowing:
TOTAL
264,547
51,057
13,097
110,229
6,684
1,792
37
,43.15
PERCENT
.
771,322
Reduction of production forest area. The shift in policy onlogging from the old growth/virgin forest where the harvestable
34.3
6.6
1.7
14.3
0.9
1.5
100.0
35
timber per ha is 110 to 153 in' to the residual/second-growth forestwhere the harvestable timber per ha is 52 in' has reduced theoperable production area and volume.
Reduction of annual allowable cut (AAC). When the policy onlogging in residual forest was enforced in 1992, log productiondropped appreciably. The 21 remaining TLAs used to have a totalAAC of 2,168,704 in' to the present 659,131 in'Expiration of TLAs. The expiration of TLAs reduced the numberfrom 97 in 1990 to the present 21 TLAs. The 21 existing TLAs as ofMarch 1998 has a total operable area of only 388,788 hectares ofresidual forests, as compared to 3,762,000 hectares in 1990. It isexpected that the number of TLAs will decrease every year due totheir expiration dates.
.
.
,
,.
Table 6.
.
Production of Processed Wood Products, Philippines,1987-, 996("000m3) , ,
Year
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
Lumber
1233
1033
975
841
726
647
440
407
286
313
Ave. /year
Growth
(%/year)
Veneer
75
85
61
49
54*
80*
65
39
19
82
Source: 1996 Philippine Forestry Statistics, FMB-DENR*Data for ARMM excluded.
3.3.2 Timber Imports
To augment the raw material supply from local sources, thegovernment encourages the importation of logs and lumber. In contrast tolocal production trends, imports of logs and lumber forthe same period (1987-1996) showed a general increasing trend (Table 7). Log imports in 1996 rosesignificantly by 26% from the 1995 level of 694,454 in' to 887,585 in' i1996. Similarly, 1996 imports of sawnwood (lumber) increased dramaticallby 50% from the 1995 level posting 567,426 in' At present, the combined
Plywood
690
(, 3.32)
517
4/5
344
397
321
331*
273
258
290
508
61
27.26
365
3.01
36
volume of imported logs and lumber exceeds the timber supply from the local
Imported timber supply come from such places as Malaysia, Indonesia,Japan, China, PNG, Solomon Island, West Africa, South Africa, New Zealand,Australia, USA, Canada, Central America and Europe. Majorit of timberused for construction come from Malaysia and Brazil.
source.
Table 7. Imports: Logs and Lumber(in'): 1987-, 996Year
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
,
,
Logs
185
490
397,926
381,178
395,239
530,026
603530
404065
694,954
877,585
Ave/yearaGrowth a
(%/yr)
Lumber
Excluding 1987 and 1988 figuresSource: 1996 Philippine Forestry Statistics.
528
2,513
12,557
3,741
9,974
43,278
462,941
298,363
378,531
567,426
3.3.3 Tree Plantations
To ensure sustainable and adequate supply of wood raw materials forthe local forest-based industries, the government has encoura ed thedevelopment of industrial forest plantations in the country. For this pur OSe,several incentives are being offered to would-be investors such as: a)Reduced payment of forest charges and land rentals; by Exemption frompayment of certain internal revenue taxes; c) Credit assistance; and d)Plantation development expenses, tax deductible.
535,563
16.12
The areas covered by plantations are found in public forest lands andin alienable and disposable/private lands. Those in forest lands areundertaken either by the government sector (DENR and Foreign Assistedprojects) or non-government entities or individuals.
222,101
In 1996, the government sector reforested/planted a total of 18,869hectares while the non-government sectors, 27,227 hectares or a grand totalof 46,096 hectares (Table 8). Forthe 10-year period (1987-1996), reforestedarea totaled 740,784 hectares or an average of 74,078 hectares per ear.
205.89
37
, Table 8. Area Reforested by the Government and Private Sectors0987-, 996)
Year
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
Total
39,811
64,183
131,404
191,663
93,039
40,593
19,211
49,551
65,233
46,096
I'
,
Government
TOTAL
Ave. /year
(%/yr)Source: 1996 Philippine Forestry Statistics, FMB-DENR.
28,843
31,226
89,452
153,949
73,602
24,304
6,347
18,032
21,841
18,869
At present, only private plantation areas are readily available for cuttingand utilization, which is about 37% of the total reforested/planted areas.Assuming a conservative growth yield estimate per hectare of 10 cu. in eryear, the available volume would be about 272,270 cu. in per year.
As of 1996, a volume of 264,547 cu. in and 6,684 cu. in, respectiveI,were produced from both IFMA/SIFMA/ITPLA and CBFMA areas (Table 6).The tree species reported to have been planted in IFMNITPLA areas areGinelina arborea, Eucalyptus deglupta, giant Leucaena Ieucocepha/a,Pareserianthes falcataria, Pterocaipus indicus, Swietenia macro hlla,Gasuarina spp. , Pinus spp. , Tectona grandis, Aleurites monucana, Oohromapyramida/e, Endospermum peltatum and other matchwood/softwood and fruittrees. Unfortunately, no statistics are available as to the volume by species.
The Philippine Master Plan for Forestry Development made projectionsof timber harvests from existing and newly established forest plantations(Tables 9 & 40). By the year 2000 and 2015, the combined total volume thatcan be harvested is estimated at 11.7 M in' and 31.3 M in' res eativelHowever, the comparative figures of actual (1996) and projected (1995)timber harvests from private/industrial tree plantations indicated a shortfall babout 50%. To realize the projected long term targets, a serious, massiveexpansion and establishment of tree plantations must be pushed.
740,784
74,078
23.59
Private
10,968
32,957
41,952
37,714
19,437
16,289
12,864
31,519
43,392
27,227
466,465 (63%)
46,646
29.49
274,3.9 (37%)
27,432
30.82
38
I
Table 9. Wood Production From Existing Forest Plantations ('000 in')LOGTYPE
Sawlog
Peeler Log
Pulpwood
Poles
Firewood
1990
378
TOTALS
1995
1511
,
542
1136
Table 10. Wood Production From New Plantations ('000 in')
lippine
1645
85
17/6
2000
3025
766
aser an or orestryDevelopment.
Sawlog
Peeler Log
Poles, localTimber
Pulpwood
Firewood
Log type
1646
127
2332
2005
3988
916
30
1645
249
2532
20.0
4871
988
110
1646
390
2767
Source: Philippine Master Plan for Forestry Development.TOTAL
const.
2015
20000
Using 50% of the PMPFD projections as basis, the combined timberharvests forthe year 2000 and 2015, is expected to be 5.85 M in' and 15.65M in , respectively. For saw logs, the corresponding expected harvests willbe 1.2 M in and 4.83 M in', respectively.
5363
108
200
1645
578
3052
1620
5901
3.3.4 Available Volume of Lumber forthe Construction Sector
Based on the volume of logs and lumber from local sources andimports, the historical (1987 - 1996) and projected/adjusted (2000-2015)volume of lumber available for the construction sector were determined asshown in Table 11.
For the period 1987~1996, it is apparent in Table 11 that the decreasein lumber supply from local sources is compensated by the increase inimports resulting in less variance in overalllumber volume available for theconstruction (housing) sector. In 1996, imported lumber accounted for about
480
1980
2820
20.5
6563
9590
2040
6900
1200
1980
9970
24780
39
I
73% as compared to 17% from local production, a clear manifestation that thePhilippines is currently a net importing country.
Actual(, 987,996) and projected (2000-20.5) lumbersupply (availability) and demand of housingconstruction, Philippinesat.
, .
Table 11.
YEAR
Supply
Local Imported" Total
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
n
1233
1033
975
841
726
647
440
407
286
313
<1
3
132
118
129
202
644
4/9
587
830
Available for
HousingConstruction
1233
1036
1107
959
855
849
1084
826
873
1143
2000
HousingDemand di
1060
891
952
825
735
730
932
710
751
983
2015
1033e/
b/In thousand cubic meters.
Logs and lumber combined (Table 7) with the following assumptions: 50% ofimported logs sawn into lumber with 60% lumber recovery.86% of total lumber volume per average (10-year) percent allocation of lumber forvarious end uses, viz. , furniture (I%), housing requirement (86%), buildingconstruction product (99'.), and secondary timber (4%) (DAP - DENR CooperativeProject. , 1989).Taken from "Policy study on wood supply and demand " Development ACadem ofthe Philippines - Department of Environment and Natural Resources Coo erativeProject. 1989.
Includes projected (adjusted) timber saw log harvests from existing and newplantations at 60% lumber recovery. Assume 1996 levels of lumber productionfrom natural forests and imports are held constant.
91
321 tel
Deficit/
Surplus
830
na
na
d/
830
na
,863e,
2702
2749
2806
2867
2942
2981
3039
91
4041E/
However, based on projections on timber (saw logs) harvests fromexisting and new plantations, local lumber production available forconstruction (housing) purposes is expected to increase from 3.267 in' byyear 2000 to 3,553 in' in year 2015. These projections are based on thepremise that lumber production from existing natural. commercial forest andvolume of imports will be sustained at the 1996 level.
40
-1877
-2014
-2976
-1935
-2232
-2230
-2056
1602
3475
3267
3553
-1665
78
3.4 LUMBER SUPPLY AND DEMAND SCENARIO FOR THECONSTRUCTION INDUSTRY
Wood consumption is expected to be on a continuous upward trenddue to the need for various end uses, i. e. , shelter and other basic necessitiesof the growing population.
The annual log requirements of existing regular sawmills and mini-sawmills are 1,952,198 cu. in and 218,532 cu. in, respectively, or a totalvolume of 2,170,730 in'. On the other hand, the active veneer and I o0dplants have an annual log requirement of 87,000 cu. in and 1,379,187 cu. in.The sawmill, mini-sawmill, veneer and plywood plants, therefore, will re uire3,636,917 in' of wood raw materials.
For 1996, comparing with the available log supply from varioussources, i. e. , natural forest (659,131 in'), imports (877,585 in'), plantations(272,270 in'), it would appear that the total available volume of 1,808,986 cu.in is not adequate to meet the log requirement of 3,636,917 cu. in. There isan apparent deficit of 1,827,931 cu. in. To overcome this, more logimportations have to be resorted; otherwise, some wood processing plantsmay have to operate way below capacity.
Based on the foregoing historical and projected data and information,we can foresee a lumber supply deficit until year 2015 unless a vigorousestablishment of additional timber plantation areas is seriously considered.
A more massive establishment of tree plantations should, likewise, beencouraged. The utilization of these species is an incentive to plantationowners/tree farmers as they will have ready fortheir produce.
IMPLICATIONS OF LUMBER SUPPLY AND DEMAND ON STRESSGRADING
The current species composition of lumber in the market includesmixed LKS/LUS from both local and foreign sources whose identities andproperties are generally wanting. In the construction industry where strengthof materials is of prime consideration, the necessity to subject said s ecies tostress grading before actual usage is a sound proposition. Irrespective ofspecies, including premium and well-known species, various lumber gradesaccording to strength classes can be produced and marketed from whereend-users or consumers can choose. The corresponding price structure shallaccountfor other consumer preferences besides strength.
The emerging future supply of construction lumber will come fromplantation-grown tree species and imports. The strength properties ofplantation species are significantly affected by age differences, source ororigin, natural defects, and inherent variability not only among differentspecies but also among and within trees of the same species. Furthermore, ithas been observed that the mixed species composition of imports from
41
3.5
various sources, which comprises about 90% of the total lumber supply, hasnot deterred the purchase of these materials for construction purposes. Inboth cases, stress grading of these materials will provide the consumers withan index of quality and price of lumber that are specified in engineered timbercomponents and structures.
Lumber remains as one of the major construction materials. Itsprojected demand for such end-use increases with population growih andexpected to be on a continuous upward trend. As mentioned in Chapter I,the current administration has targeted to build 1.15 M housing units from nowuntil 2004 and with the inflow of lightframe, panelized and other industrialsystems, the demand for lumber is expected to increase. While we foresee alumber supply deficit until the year 2015 Of the rate that plantations areestablished will not improve), it is projected that starting year 2005 thehousing lumber supply and demand may be met and sustained in the longterm. The Exports Development Council(EDC) has embanked on developingI million hectares of tree plantations, as well as, importing timber to supplythe requirements of the wood-using industries (Dupaya 1996). Moreover, thecurrent volume of lumber available in the market is still significant, thus, stressgrading may be warranted as this will redound to more efficient and scientificwood utilization thereby lessening the pressure on the remaining timber stand.Stress grading should be implemented with a package of incentives toencourage the establishment of more tree plantation farms.
,I
42
Chapter 4
EXPLORING THE ECONOMIC FEASIBILITYOFLUMBER STRESS GRADING IN THEPHILIPPINES
I
4.1 INTRODUCTION
Investment decisions are based on an evaluation of a pro OSedproject's technical, market, financial and economic viability. Fortechnolo iesor processes with functioning markets, assessment is straightforward andpresents few complications because there is access to price and market data.
In the Philippines, stress grading is a new concept and stress-gradedlumber, either visual or machine graded, is not available in the market. Theabsence of concrete technical and price information makes it difficult to buildrealistic assumptions on which to base a definitive analysis of the benefits andcosts of stress grading. As part of a larger pre-project initiative whichexplores the prospects of developing and implementing stress grading rulesfor tropical timbers in the Philippines, this study attempted to provided ananalytical framework for assessing the economic benefits and costs of stressgrading and the alternative methods to assess its economic feasibility.
In general, the study explored the economic framework for determiningthe feasibility of stress grading lumber in the Philippines. Specifically, thestudy attempted to address the following objectives:
To describe the present system of lumber production, grading andmarketing and determine the points where stress grading mayapply.
. To identify approaches/analytical techniques for determining theeconomic feasibility of stress grading, and
. To examine the potential economic benefits and costs associatedwith stress grading.
,
.
*
4.2 METHODOLOGY
4.2. , Conceptual Framework: The Economics of Stress Gradin
Grading is the process of sorting or separating a homogeneous productin accordance with a predetermined grading scheme. Grades, on the other
43
hand, are subdivisions of product classes defined by attributes, ina nitudes,and ranges or tolerances.
Pinhus Zusman (196_), lists three factors which may give rise tograding and sorting:
'The sale of unsortedproducts involves certain constraints on bu er^ freedomof choice. If only unsorted products are being offered on the market, bu ersare forced to purchase a product consisting of a predetermined combination ofthe homogeneousgrades.
a. The existence of established standardized grades' removes inari of theuncertainti^s inherent in eXchange. Unless products are sorted intostandardized grades, buyers are ignorant of the product composition and eachtransaction is beset with uncertainty.
b. Grading andsorting may serve sellers in obtaining certain mono o1 ams.Grading and sorting may be instrumental in establishing certain types of ricediscrimination andproduct differentiation by sellers "
Sorting a homogeneous product into classes with similarcharacteristics provides consumers with choices on which to make informeddecisions. Specifically, sorting lumber into groups with specific stren thproperties affords an opportunity for consumers to purchase and use lumberwith a guaranteed capacity to carry a specific load.
Grading alters product quality. Generally, a graded product is pricedhigher than the ungraded lot. This is due not only to the costs associated withgrading and sorting but also to the higher value usually attached to "qualit ".Grading provides an opportunity for a firm to increase total revenues. Anchange that will add more to total receipts than to total costs will increaseprofits. Thus, a firm will resort to grading if its profits will increase as a resultof grading its products.
. There are economic incentives from stress grading of lumber if thericedjfft'Ibt g eprice differential between the stress-graded lumber and non-stress- radedlumber exceeds or at least equals the additional cost of stress grading, that is,
PSGL ~ PNSGL ^; CSGwhere,
PSGL ' per Unit price of stress-graded lumberPNSGL ' per unit price of non-stress-graded-lumber
CSG ' cost of stress grading a unit of lumber includingnormal profit
Under competitive market conditions, in the long run, the price differential willjust equal the cost of grading.
.
4.2.2 Analytical approach
A review of the prevailing institutional, production and marketinsituation and the current lumber grading system is first presented to highlightthe environment in which the potential benefits and costs are expected to
44
arise. The potential points in the present system where stress grading maybe introduced are also identified.
Based on the above conceptual framework, alternative approaches forassessing the economic feasibility of stress grading lumber are discussed.
Finally, an examination of the potential benefits and costs of stressgrading is made. Being exploretory in nature and due to lack of market, priceand cost data, a quantitative assessment of costs and benefits was notpossible during this pre-project stage, hence analysis was largelydescriptive/qualitative in nature.
4.2.3 Sources of Data
The analysis presented in the study was based on data obtained fromliterature, from consultations with industry representatives and from interviewsof lumber producers and traders.
Several consultations with representatives of the Philippine WoodProducers Association (PWPA) were held to obtain a perspective on theprimary wood processing industry.
Questionnaires were prepared and sent to 17 sawmill operators.Response rate was 23%. Ten lumber dealers were also interviewed in LosBanos, Calamba, Sari Pablo and Sta. Cruz. Field observations on actualsawmilling operations were also made in three sawmill sites. The twosawmills are located in Misamis Oriental and one is in Metro Manila.
4.3 RESULTSANDDISCUSSION
4.3. , The Present Marketing System
The present system of lumber processing and sorting of lumber in themills, as well as pricing of lumber were presented earlier in Chapter I (SeeSection 1.1).
The primary sources of lumber are the sawmills and lumber importers.Lumber from these sources are distributed either through traders or direct toconsumers or end-users such as furniture manufacturers, building contractorsor small house builders (Figure 16).
End-users may sometimes have specific needs that are not ordinarilymet in commercially traded lumber. These may be lumber, kiln dried (KD)toa specific moisture content, lumber cut to specified dimensions, lumbertreated with preservatives or lumber of a specified species only. Thesespecifications are relayed backwards down the marketing chain by end-usersto their suppliers.
45
I
LUMBER
IMPORTERS .-.-.-.-.-.-
"
SAWMILL
OPERATORS
LUMBERTRADERS
productllow
information flow
<.. ,
A
Large sawmills have the facilities and the capability to provide for thesevarious customer requirements. Some lumber dealers also have kiln dryers tomeet orders for KD lumber. Stress grading, as an additional marketingservice may thus be introduced at two points in the marketing chain---at theorigin, i. e. , in the sawmill or in the stockyard of lumber importers, or at thetraderlevel. In the sawmill, stress grading may be done after air- or kiln-drying the lumber. At the trader level where lumber is often delivered airdried, stress grading may be done immediately, unless kiln drying is specified.Lumber dealers may also offer, for a fee, the use of their stress gradingmachine to other lumber dealers or to customers who may wish to stressgrade their own lumber.
Figure 16 Product and information flow for lumber
.
<
END
USERS
Alternative Approaches in Assessing the Economic Feasibility ofStress Grading
Project analysis involves the assessment of the financial and economicviability of the proposed project. These two types of analysis are closelyrelated because both are conducted in monetary terms, the major differencelying in the definition of costs and benefits. Economic analysis attempts toassess the overallimpact of a project in achieving the national economic
46
4.3.2
objectives of the country concerned. Benefits from a project constitute theextent to which the end-product contributes to the achievement of nationalobjectives. Costs reflect the degree to which the achievement of thoseobjectives is sacrificed by diverting the resources required by the project fromalternative uses.
Financial analysis evaluates the project from the viewpoint of theproject entity or from the investor; that is, all expenditures incurred under theproject and revenues resulting from it are taken into account. This form ofanalysis is necessary to assess the degree to which a project will generaterevenues sufficient to meet its financial obligations. Applied to stress gradingfor lumber, the analysis will determine whether sawmill operators and lumbertraders who will adopt stress grading and trade stress~graded lumber willrealize net gains after accounting for all the costs associated with stressgrading.
In financial and economic analysis, benefits exceeding costs is ageneral indication that the project is financially or economicalIy feasible and isworth undertaking from the financial or economic point of view.
4.3.2.1 Stress Grading as an Additional Operation in the SawmillUsing Partial Budget Analysis
Stress grading is an additional process in lumber production. As acomponent of the whole sawmilling operation, the technology can beassessed by applying the principle of partial budgeting. In the analysis, onlythe revenue and costitems affected by the proposed change are considered.Ad
A sawmillthat decides to stress-grade its lumber output will have tomake additional investments. If visual stress grading will be used, investmentin training of the workforce is necessary to achieve a high level of accuracyand efficiency in grading lumber. If both visual grading and machine stressgrading will be done, an additional investment would be a stress-gradinmachine. In Malaysia, the equipment being considered for stress gradingcosts around $Us 150,000 to $Us 200,000. An Australian-made machinesells for about $Us 100,000; another machine made in South Africa sells forabout $Us 20,000. '
FPRDl, on the other hand, has developed a manually operated stressgrading equipment which can be fabricated for only $Us 763. Estimated costof upgrading this to meet a more mechanized operation is Us$ 2,500'excluding an automatic loading and data acquisition systems and calibrationgadgets.
I n 11nves men
. From a June 1998 correspondence with Robert Leicester, CSIRO, Australia.As estimated by a local machine fabricator in Manila, July 1998.
47
Added Costs and Returns
The added costs of producing stress-graded lumber can be brokendown into equipment cost, labor cost, utilities and interest. The cost of astress-grading machine is expressed in average annual values ordepreciation. Depending on the workload, additional workers may be hired tohandle increased sorting activities. What is important, however, is that theworkers assigned to stress grade should be competent enough to ensure thatstandards are met. Additional expenses for electricity and repairs andmaintenance of the equipment will also be incurred. And lastly, interest on thecapital investment of the firm will also have to be included as an added cost.These additional costs have to be compared with the expected additionalreturns.
For a given volume of lumber, it may be expected that returns from thesale of stress graded lumber will be greater than that for ungraded lumber.The difference is attributed to the value attached to "quality" which is now anadded feature of the stress graded lumber.
The difference between added costs and added returns is the netchange in profits of the sawmill. Profits will increase if the additional return isgreater than additional costs. This can be shown by the following:
,
WithoutStres Gradin
R, = r, - c, where,
Rn = netrevenue from sale of non-stress graded lumberr" = total revenues from sale of non-stress graded lumberc" = cost of producing non-stress graded lumber
With Stress Gradi
Rs = rs- CS where,
Rs = netrevenue from sale of stress graded lumberrs = total revenues from sale of stress graded lumberCS = cost of producing stress grading lumberAdded netrevenues from stress grading is:V = R, - R,
For stress grading to be profitable,V > O
48
Table 12 shows the components of the analysis.
Table 12. Estimating the change in profits for a given volume oflumber, as a result of stress grading
,
ITEM
A. Additional Returns
B. Additional Cost
Equipment
Labor
Power
DESCRIPTION
Repair andmaintenance
Interest
Difference in total revenues between stressgraded lumber and non-stress graded lumber
Expressed as average annual values or depreciationWages of additional workers assigned to the stressgrading operation
Increased power consumption due to operation ofthe machine
Additional expenses to cover machinerepair and maintenance
Interest on the additional investment made
Difference between additional returns and additionalcost
C. Net Change
Cost ridRetums ofPr d Gin Sress Gr
Table 13 illustrates how stress grading can affect the cost and returnstructure of a sawmill. Estimates of costs and returns for lumber production ofhardwoods were based on lumber production data for Gineiina (Gine/Inaarborea) and on prices of sawlogs and lumber taken from the 1996 Philippineforestry Statistics. Since prices vary markedIy between regions, estimatedcost and returns of lumber production in Region IX and Region XI are alsoshown. While there is, as of yet, no basis for estimating the additional cost ofstress grading in the Philippines, it is believed that a 50% addition isconservative.
With these assumptions, net income will decrease by 37% in region IXand by 809', in Region XI, .. if unaccompanied by an increase in the selling priceof lumber. Forthe sawmill to maintain profits at pre-stress grading levels, thecost of stress grading could be passed on to consumers in the form of ahigher selling price---P20.88 per bdft in Region IX and P26.30 in Region XI.Further increasing the selling price will generate additional profits. Theacceptability of stress graded lumber at increased prices should, however, befurther examined through a market survey.
e Lu ber
49
Table 13. Comparative Cost and Return Structure of LumberProduction, With and Without Stress Grading, in PIbdft
ITEM Productionof lumber
from
Ginelinaa
COSTS
Raw
material
ProductionCost
REVENUEd
WITHOUT
STRESS
GRADING
,
RegionIX
NET
INCOME
6.80
3.00
.
12.97
3.75
RegionXI
WITH STRESS
GRADING,No price increase
Stress Grading as an Investment Option for SawmillersUsing Investment Analysis
Partial budgeting is a simple analytical tool when investments arerelatively small and data are limited. When long-term and substantialinvestments are being considered by a firm, such as the purchase of complexequipment, partial budgeting no longer provides a long-term view of a firm'sfinancial gains. An alternative approach is investment analysis, which looks ata firm's inputs (costs) and outputs (benefits) over time. Some indicators ofeconomic feasibility are discussed below.
4.3.2.2
18.00
15.72
3.75
RegionIX
8.20
I9.00
12.97
5.63
RegionXI
WITH STRESS
GRADING,With price increase
2.28
24.42
15.72
5.63
RegionIX
4.95
Pa
19.00
The payback period is one of the simplest and commonly usedmethods of investment appraisal. Applied to a sawmill's investment in stressgrading, it is defined as the period required to recover the investment madeon the stress grading machine through the accumulated net cash flowsearned by producing and selling stress graded lumber. A short paybackperiod corresponds on average to a high annual net cash flow while a long
ak
12.97
5.63
RegionXI
0.40
24.42
ri d
15.72
5.63
3.07
20.88e
' Taken from a feasibility study on the production of lumber from Ginelina by ForesterFrancisco Lapitan, 1996Based on prices of mixed grade sawlogs in Regions IX and XI, taken from the 1996Philippine Forestry Statistics
' Covers cost of labor, utilities and depreciation; for production of lumber from hardwoodsthis cost item is assumed to be higher by 25 % than for Ginelina; an additional 50% isassumed with the introduction of stress gradingSelling price of lumber per bdft. ; adjusted for Regions IX and XI based on retail pricestaken from the 1996 Philippine Forestry StatisticsFor Regions IX and XI, the selling price of lumber at which the producer will not experienceany loss in net income
50
2.28
26.30
b
4.95
d
e
payback period implies that the ratio between the annual net cash flows andthe initial investment is relatively poor. This method does not take intoaccountthe performance of the plant after the investment is recovered
N t Present Value
The net present value of an investment is defined as the valueobtained by discounting, at a constant interest rate and separately for eachyear, the net cash flows accruing throughoutthe life of the project.If the computed NPV is positive, the profitability of investing in theproduction of stress graded lumber is above the pre-determined cut-offdiscount rate. If it is zero, the profitability is equal to the discount rate. IftheNPV is negative, the profitability is below the cut-off rate and the projectshould be dropped.
NPV
Internal Rate of Return
The internal rate of return is the discount rate at which the NPV is zero.The IRR may be interpreted as the highest net-of-tax annuity rate at which astress-grading project could raise funds, provided the annual net cash flowsfrom the project are rather constant. Investing in a stress-grading project maybe accepted if the IRR is greater than the cut-off rate, which is the lowestacceptable interest rate forthe invested capital.
Marketing Margin Analysis for Assessing Benefits andCosts for Lumber Traders
The previous discussions focused on the measurement of the financialgains or benefits of stress grading, from the point of view of the sawmill. Butsince it was earlier identified that stress-grading can also be done by traders,the profitability of stress grading at this level should also be examined.
Marketing of stress graded lumber will most likely follow the currentdistribution channels, i. e. ,it may either pass directly from the producer to theend-user or it may be bought and sold several times before it reaches theconsumer. These buying and selling activities are undertaken by traders.The difference between the price at which a trader buys stress-graded lumberand the price at which he sells it is called the marketing margin.
Aside from transporting and storing lumber, the trader may incur othercosts such as promotional costs and additional sorting costs. His net profitfrom selling stress-graded lumber will be the difference between his marketingmargin and the added cost of marketing stress-graded lumber. The trader'snet profits will increase if the net profit from selling stress graded lumberwould be greater than his net profit from selling ungraded lumber. Theserelationships are expressed in the following equations:
4.3.2.3
5 I.
Net Profits from Stress Graded Lum er
,
Net Pr fits from Non-stress Grade
Marketing Margin sGL = Selling Price sGL-Buying Price sGLNet Profit sGL= Marketing Margin sGL-Cost of Marketing sGL
Marketing Margin NSGL= Selling Price NSGL . Buying Price NSGLNet Profit NSGL = Marketing Margin NSGL - Cost Of Marketing NSGLTraders' profits will increase if Net Profit sGL > Net Profit NSGL
4.3.4 FACTORS AFFECTING THE VIABILITY OF STRESS GRADING4.3.4.1 Demand
The need to initiate a project on stress grading has been clearlydefined in earlier documents. Butthe need for a project does not alwaystranslate to demand. While needs are often defined on the basis of whatauthorities consider to be necessary forthe population, demand, on the otherhand, reflects whatthe target population is prepared to pay for.
For demand for stress-graded lumber to materialize, it must beperceived as having value. That additional value must be translated in termsof a higher price for stress graded lumber that consumers must be willing topay for. The target market should accept it and there must be ability andwillingness to pay on the part of industry and consumers. Cultivating demandfor stress graded lumber starts with informing the target market of what stressgrading is all about and what it can do for them. If demand does riotmaterialize and there is no perceived and actual value added, then a pricedifferential between stress graded and non-stress graded lumber will not exist,and no economic incentives can be derived from stress grading.
4.3.4.2 Sustainability
Sustainability is an important issue in any project. As a new concept,stress grading has certain ramifications that should be taken into account forsustainability to be achieved. For one, adjustments in the curricula of Civil
SGL
Lu r
Engineering and Architecture courses have to be made so that stress gradingconcepts can be better appreciated and applied in actual projects. Copies ofcivil and forestry engineering course outlines obtained from four leadingnational universities indicate that the coverage and time allotted to the topicon stress grading and the structural use of timber in engineered structures areinadequate.
Information on the properties of LKS and imported species should begenerated to complete the technology package on stress grading. Withoutadditional information on the mechanical properties of lessenused species,the advantages of using stress-graded lumber cannot be fully realized.
52
Equally important are the availability of technical personnel, suitabilityof the grading scheme to market needs, appropriateness of the technology toactual industry conditions and the availability of facilities to monitor, repair andmaintain stress grading equipment.
4.3.5 POTENTIAL ECONOMIC BENEFITS AND COSTS OFIMPLEMENTING STRESS GRADING IN THE PHILIPPINES
Cost-benefit analysis involves a numerical comparison of the costs andbenefits of a project, provided that both can be quantified. Whenquantification is not possible, the analysis may be described in qualitativeterms.
Benefits and costs of stress grading have been sufficiently discussed inprevious ITTO reports, particularly on the development of harmonized stressgrading rules. The discussion below takes after that report buttouches on thePhilippine situation.
4.3.5.1 Benefits of Stress Grading
Conservation and sustainability through efficient utilization of timber.
Conservation can be achieved not only by refraining from using aresource, as in the case of the logging ban, but also by efficiently utilizing it.This aspect of conservation will take on greater importance when the woodindustry eventually returns to the second-growth forest forthe next cycling cut.Since the volume of timber to be harvested is much less than in the oldgrowth forest there is a need to utilize these resources efficiently.
The use of stress-graded lumber, particularly for construction purposeslead to a more rational use of wood, which is still the predominant
material for houses and small buildings. Although the use of substitutes suchas aluminum and steelis becoming more popular in the urban areas, wood isstill commonly used fortrusses, wall and floorframes, beams and posts in therural areas.
Using stress graded timber for housing components such as rooftrusses can generate savings in the use of wood. Often, experiencedengineers who are asked to prepare engineering and architectural plans tendto specify the same sizes of wood for various house components as inprevious projects. To illustrate, it has been customary to specify 2pcs of 2" x4" guyo (Shorea spp) bottom chords and I PC guy0 2"' x 4" as top chord and2" x 2" guyo web members fortrusses of houses and small buildings. Whenguyo is not available in the market, owners would agree to replace this with
resources
can
the available lesser known species, bokbok IXanthuphylum excelsum (Blume)Miql for example, however increasing the sizes of bottom and top chords to 2"x 6" and the web members to 2" x 3". Some LKS species are compareble in
53
strength such as in this case or even better than premium species butconsumers purchase bigger sizes needlessly for fear of providing inadequatestrength substitute but lesser-known species. To illustrate, a certain trussdesign for a 36 square meter house was assumed as basis for computations.This design will utilize about 38.66 bdft of either guyo or bokbok. Whenincreased size bokbok is used for reasons mentioned earlier, 8.66 bdft pertruss or 60.62 bdft per housing unit is used needlessly. This figure may riotbe substantial on a per house basis but it becomes significant considering thatthe current administration is targeting to build 600,000 units annually,assuming perhaps that 50% will use timber trusses.
. increased confidence in the use ofLKS andimportedtimberspeciesIndustry sources estimate that 909', of the lumber available
commercially is imported. Consumers are thus left with very little choice butto use these fortheir construction needs. The common problem that is oftenheard by lumber dealers regarding imported species is the unfamiliarity oflocal users with the properties of these species. Stress grading providesconsumers with information on the load bearing properties of these species,giving them assurance of the best and most economical lumber for theirrequirements.
This advantage extends to the lessenused species. As of 1996, thecountry has 2.81 million hectares of secondary or logged over dipterocarpforest, composed predominantly of LKS and miscellaneous tree species(Manila, A. 1998). Estimated volume from this area is 57,932,000 cubicmeters. Knowledge of the strength properties of these LKS will increase itsuse, thus lessening dependence on the diminishing traditional and moreacceptable wood species. Assuming that most of these are not presentlyutilized, stress grading can potentially increase the utilization rate of thesespecies and thus save foreign eXchange forthe country.
. Adds value to lumber and engineered housing components
Stress grading gives the added dimension of quality to lumber, afeature lacking in the present mix of wood species in the market, particularlythe LKS. Through effective marketing, a premium can be placed on stress-graded LKS, thus increasing their value.
Stress graded lumber paves the way forthe introduction of engineeredhousing components and makes their acceptance easier. The use ofprefabricated components with lumber as structural and architectural framesused in industrialized systems for construction has been introduced in masshousing projects. Their acceptance will be facilitated by the assurance thatquality timber is used. Stress grading thus offers a marketing opportunity forsawmills and manufacturers of pre-engineered housing components.
54
4.3.5.2 Costs of stress grading
The benefits from stress grading may riot materialize unlessaccompanying investments are made. Education, R & D and technologytransfer are activities aimed at eliminating barriers to the adoption and use ofstress graded lumber.
. Education
The use of lumber for construction has its roots in tradition. Even forsome licensed engineers, timber construction is often based on rules-of-thumb. Creating awareness and developing an appreciation for stressgrading would thus be the initial task of project implementors whose practiceis sanctioned by the Philippine Domestic Construction Board under theConstruction Industry Authority of the Philippines. Continuing Educationseminars on lumber stress grading should be required by the ProfessionalRegulations Commission for practicing Civil Engineers and Architects. TheFPRDl, CIAP and the Bps should encourage private professionalorganizations such the Philippine Institute of Civil Engineers (PICE),Association of Structural Engineers of the Philippines (AsEP), and the UnitedArchitects of the Philippines (PICE) to conduct such seminars in their variouslocal and national chapters and members can earn the required credit unitsforthe renewal of their licenses.
The three sawmill operators and ten lumber dealers interviewed in thesurvey stated that they were satisfied with the present system of grading.This response, however, seems to stern more from ignorance of a better
alternative rather than from the perceived absence of problems.
An intensive information campaign should aim at developing anappreciation for stress grading for the wood processing industry, civilengineers, architects, carpenters and the general public. A handbook ontropical timber engineering should be prepared.
Investment in education includes development of curricula for degreeprograms and offering of short-term training courses for upgrading of andacquiring new skills for workers and staff.
. Researchanddevelopment
In the Philippines, the groundwork for research on stress grading hasbeen laid by FPRDl. It has conducted initial studies on a concept of aspecies-dependent stress grading. But research on this is by no meanscomplete, as much of the earlier work needs further validation.
Apart from the stress grading technology, information on the physical,mechanical and wood working properties of LKS should be generated throughresearch. These are technical information necessary to optimize the use ofstress graded lumber. Since most of R & D is a public expenditure,government will have to bear a large part of this cost.
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. Technologytransferandpromotion
An equally important task is the promotion of the developed stressgrading technology to the target markets. This activity should aim atconvincing the wood industry to produce stress graded lumber and for theend-users to use it. Incentive packages specially for producers and tradersshould be devised to facilitate the promotion of technology.
4.4 IMPLICATIONSOFECONOMICSTUDIES
This pre-project study, as an exploretory study, examined the analyticalframework for assessing the economic feasibility of stress grading andpresented the expected benefits from stress grading and the costs associatedwith its implementation and adoption and the conditions necessary to realizethe identified benefits. Due to lack of market, price and cost data, it did riotpresent conclusive evidence that can be used to categoricalIy state thatstress-grading is or is not economicalIy viable.
Benefits of stress grading lumber for structural use can be realizedunder assumptions of product acceptability and market demand.Transforming these assumptions into reality, though not irisurmountable, willtake time and expenditure of considerable resources. For projectimplementors, the initial task should aim at eliminating information and culturalbarriers that stand in the way of its adoption and use. For potential investorslike sawmill operators and lumber traders, determining the economic viabilityof a stress grading operation will involve a deeper examination of the followingaspects:
. Marketanalysis
It is important to have a firm estimate of the demand for stress-gradedlumber to fully appraise its viability. This activity will also gauge the reactionof the market to the stress grading concept. Forthe potential investor, thisdemand will have to be matched with potential volume of stress gradedlumber that can be made available for sale.
. CashflowProjections
After establishing various technical parameters related to stressgrading, detailed projections aimed at determining the actual financialcontribution of stress grading to the firm's profits should be made. This wouldrequire data on the grading scheme to be introduced, the volume orproportion of lumber that will be made available for each grade, the price perunit of lumber corresponding to each grade in the grading scheme and thecost of grading, sorting and marketing of stress graded lumber.
. Activities aimed at creating demandandachieving sustainabMtyStress grading is a totally new concept to a large proportion of the
target market. The major activities of a project on stress grading should
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address this lack of awareness among target beneficiaries with the end goalof creating demand and should setthe groundwork for attaining sustainability.
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Chapter 5I
MARKETASSESSMENTANDSTRATEGIES ONTHE IMPLEMENTATION OF STRESS GRADINGRULES FORTROPICALTIMBERS IN THEPHILIPPINES
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5.1 INTRODUCTION
A visibly dynamic environment has engulfed timber trade situationsespecially in traditional producing countries in the developing regions of theworld. Continuous depletion of forest resources with its accompanying socialeconomic implications has resulted in export bans on selected forestproducts, intensified programs, replanting and plantation establishments andemphasis on local processing of high value products. Certainly, a moreefficient and judicious use of existing wood resources deserves an urgentattention.
Mechanisms and strategies considered ideal on country-to-countryapplications are being put in place to reduce pressure on timber extraction. Apotentially effective mechanism could be the development andimplementation of stress grading rules fortimbers. The beneficial effects ofstress grading have become obvious, e. g. , conservation of resources,sustainability, more efficient use of material, production of value-addedproducts and better returns. Elsewhere, these advantages may have beenrecognized. Seemingly, however, there could be restricting elements whichhave for a long period of time characterized the implementation of stressgrading procedures. The varied factors need to be identified and overcome ifthe full benefits from stress graded timbers are to be realized. In thePhilippine context, there appears a dearth of information on stress grading oftimbers as far as practical or commercial application is concerned. Thesoundness of implementing stress grading rules remains uncertain as theviability of producing graded timbers is not clear. Of course, the bottom lineof allthese apprehensions is the marketability of stress-graded materialsintended for construction purposes. If market exists either in realterms orhas potential evidences, then the preceding chain of stress gradingprocedures will automatically react to meet market demand. Establishment of
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markets, though, has its own ramifications which require a more systematicand in-depth analytical approach.
This pre-project attempted to assess, in the local perspective, themarket potential of stress-graded timber for construction purposes. Themarketability analysis took cognizance of the magnitude of potentialunloading points for the graded products as well as the business appeal inproducing them.
The second objective was to conceptualize promotional approachesthat could lead to the popular adoption of stress grading rules and ensuresale of graded timbers.
5.2 REVIEWOFLITERATURE
There is more than just stating that marketing denotes the flow ofgoods from the production side to the consumer end. Successful marketingdoes not and cannot happen by chance. A comprehensive analysis of allinteracting elements is always imperative, e. g. , characteristics of themarketplace, product identification, marketing, marketing channels ordistribution systems, sustainability of supply and the existing businessenvironment. On most cases, therefore, policies and programs are set inmotion to ensure the right market climate.
Highly reliable and precise market information is indispensable in anymarketing strategy formulation. Eastin (1996) cited many instances ofproducts failing to gain access in the marketplace owing to lack or inadequatemarket information. Experiences seemed to indicate that product failureswere mainly attributed to insufficient market knowledge and misdirectedmarketing strategies. In an extended study of product failures, Webster(1993) as reported by Eastin, attributed such failures to a number of factorssuch as failure to focus on a specific market segment, underestimating themarketing effort required and inadequate knowledge of the buying process.
Borzatta (1992) strategized a procedure on how the ASEAN timberindustry could possibly penetrate the European market. He stresses thesepoints: an analysis on why the ASEAN producers should enter the hugeEuropean market for furniture and value-added timber products;identificationof the characteristics of the problem; discussion of the specific characteristicsof the market and suggestion on entry strategies. The marketing strategyconcluded with some recommendations that included organizational changes,expatriates management and overcoming of cultural barriers.
Insights into the application and marketing of stress grading of timbersin the three major tropical timber producing regions in the world were aptlydescribed in an International Tropical Timber Organization (ITTO) document(1991). The report presented the potential areas for increased application ofstress-graded materials. However, marketing constraints existed in theregions subjected to study. Apparent lack of market was discouraging
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producers to turn out stress-graded timber even ifthey were capable of doingso, The situation conforms with the basic marketing philosophy whproduce when there is no taker? It should be noted that in countries wherestress grading rules were available, there were claims in the consumer side ofthe unavailability of stress-graded materials. There seemed to be indicationsthat the producers were willing to engage in the production of stress-gradedtimber provided there was market certainty. Market assurance, however, wasdifficult due to the competitions offered by lowercost, non-wood alternatives.
In the Philippines where there is no stress grading rules in effect, themarket for stress-graded timbers for construction may be realized by carefuland systematic selling of the whole stress grading concept. On the issue ofstress grading implementation, the opinion of the Philippine Wood ProducersAssociation (PWPA, 1998) is that the critical matter does not involve theconcept itself but rather on how effectiveIy the idea can be communicated.Engineers, architects and designers need to be educated and convinced onthe value of stress-grading in order to create the desired market. The PWPAcan sustain supply of stress-graded timber if there is an assured market,practically echoing the ITT0 (1991) report. General awareness of the
grading procedures and allthe art and skills of imparting them will play a keyrole in the successful implementation of stress grading and marketing ofstress-graded materials. Marketing becomes simple as long as the end-usersare getting their money's worth and the producers are getting extra somethingout of it.
5.3 METHODOLOGY
5.3. , Market Potential Analysis
An analysis was made on the size/volume of potential directconsumers/beneficiaries of stress-graded timbers in the local context. Thepotential demand, the sustainability of raw material supply to meet expecteddemand and the interplay of favorable factors were alltaken into account.
5.3.2 Marketing Problem Characterization
Attempts were made to identify possible barriers to the successfulmarketing of stress-graded materials. Constraints could be social, economic,cultural or technical in nature. On the other hand, even if a market has beenestablished, inadequate or uncertain supply of products could pose a seriousproblem from the sales standpoint.
5.3.3 Market entry Modes/Strategies
Based from the information generated on the perceptions and attitudesof the timber processing sector, construction industry, direct consumers andconcerned government agencies, logical and practical marketing strategieswere suggested. The action plan incorporated the marketing channels
though focus was on a intensified networking and promotions.
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5.4 DISCUSSIONS
5.4. , Market Potential Analysis
The Philippines is widely acknowledged as having a bright economicprospect. Economic indicators tend to bear this out. In 1997, the GrossNational Product (GNP) reached an estimated high of 2.6 trillion (Anon. ,1998). During the first three quarters of that year, GNP increased by 6%which is already at the upper end of the 5.5% - 6% revised projection.Impressive figures have also been registered in the area of investments andexports. The Department of Trade and Industry reported that the countsurpassed its 1997 P 550 billion investment target as early as Septemberwhen investment hit P 613.2 billion or 11% higher than the year's tar et. Interms of exports, $ 20.6 billion worth of goods was posted during the first 10months of 1997. These earnings actually surpassed the exports registeredfor the whole of 1996 and just $ 5 billion short of the 1997 target of $ 25billion.
Owing perhaps to political stability and other favorable factors, thePhilippines gained the distinction of being one of the few countries that wereless affected by the economic crisis that hit its neighboring governments.Prospects are looking good for it to become the newest economic tiger in thispart of the world.
5.4. , ., SizeNolume of Stress-Grade Lumber
The country is home to some 70 million people with an estimatedannual growth rate of 2.3%. As far back as can be remembered, a mostpressing and formidable challenge of the government is finding a way toprovide decent and affordable housing to the burgeoning population. Atpresent, there are about 3.7 million Filipino households that need shelter,79% of which are located in the urban areas (Dupaya 1997). Under thePhilippine setting, the number of households will have a higher growth ratethan population owing the new patterns of household formation. Ultimately,Filipino households will be made up of nuclearfamilies and single persons'
With the above scenario well in the minds of the national leadershi ,the government has considered housing as a national priority. The NationalShelter Program (NSP) is the government's lead program on housing whichaims to providing housing assistance to some 1.2 million households duringthe period 1993-1998. Ifthe government has to solve the 3.7 million housinbacklog at an average cost of P 150,000 per housing unit, it has to set asideabout P 560 billion (An on. 1997a). Under the supervision of the government'sHousing and Urban Development Coordinating Council, the NSP hasprovided housing assistance to some 786,000 families during the period1993-1997 involving over P 107 billion of investments (Anon. 1997b).
Certainly, a lot more has to be satisfied in terms of providing housingespecially to the low-income Filipinos. It is estimated that the housinbacklog will widen in the next five years, The existing demand forthe low-cost housing at present is about 600,000 units annually with the average
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supply standing at ohly 175,400 (Anon. 1997c). The Estrada administrationexpects to build 1.15 million affordable homes between now and the ear2004 to cutthe huge housing backlog and Which will serve as a Ie ac to thepresident's campaign pledge that was mounted on a policy of povertalleviation.
Generally, the Philippines' construction sector has shown impressiveperformance in recent years, During a given period in 1997, the sectorregistered a growth of 15.2%, much higher than the 9.9% increase it OStedduring the same period in 1996 (Anon. 1997d). In 1996, the total number ofbuilding permits issued reached more than 93,000 or some 23% more than in1995. Total investments in these projects reached PIO2 billion which is twicethe amount spent in the previous year. While the agriculture andmanufacturing sectors suffered declines in 1997, the construction industwas able to survive the economic slowdown and continued to chalk usignificant growth. The Board of Investments, as part of the 1998 investmentpriority plan, required industrial community projects to devote 25% of the totalgross area to the development of affordable housing so that they could availof incentives such as a four~yeartax holiday. An industrial community refersto a large tract of land for development with carrying capacity for townfacilities such as accommodation, multi-purpose centers, health centers,drugstores, schools and livelihood centers.
Considering the prevailing situations in the housing and constructionindustry, the market for construction materials is far and wide and vastprospects exist forthe application of stress-graded timber.
5.4. , .2 Sustainability of Raw Material SupplyA guarantee of sustained supply will play a key role in the successful
marketing of a particular commodity. Any attempt, therefore to build up aconsumer base will have to be dovetailed with an assurance of continuousflow of goods to meet demand. In the case of stress-graded timber, it isimperative to assess the availability of wood species to be stress-graded.
The local timber supply situation is discussed in Chapter 3. It is shownthat log supply is provided by three major sources. Firstly, the natural foresthas been the traditional supplier of logs to meet local demand. Sizeable
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areas for commercial exploitation still remain with standing volume ofextractable timber estimated at more than 400 million cubic meters (M cu. in)as of 1996. It should be noted, however that log production from thecommercial forests has significantly gone down owing to the protection andconservation policies of the national government. For instance, during theperiod 1986-1995, production of sawlogs/veneer logs reached a eak of 3.4M cu. in in 1997 but dipped to just 0,589 M cu. in in 1995 (DENR, 1995).
Another source of wood for local processing is the plantation forest.Thisish "This is shaping up as a very promising supplier of raw materials consideringits environment friendliness and the serious and massive efforts of bothgovernment and private sectors towards the establishment of plantations all
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overthe country. Rate of establishment is close to 80,000 hectares a yearand the total area reforested during the period 1986-1995 is almost 800,000hectares. By conservative estimates, around 0.27 M cu. in. per year of timberis extractable from private plantations alone. The annual harvest is expectedto pick up as more and more areas are reforested.
With the current government control measures on logging incommercial forests coupled with the yet growing plantation resources, itbecomes obvious that local log supply can never meet the demand of adeveloping economy. Thus, timber imports appear to be a favorite option.Import figures are almost phenomenal. From just 49 cu. in for logs and 3.7cu. in for lumber which were shipped into the country in 1986, the volumesshot dramatically starting in 1987 and in 1996 or 10 years after. Logs andlumber importations were recorded at around 0.87 M cu. in and 0.57 M cu. in,respectively.
Timber self-sufficiency, however, may not be a far-off dream for thelocal wood-using industries. In the area of tree plantations, plans are in placeto make them contribute better to economic development. As early as 1996,for example, the multi-sectoral Export Development Council(EDC) has beenlooking for a $ I billion fund to be placed in the potentially lucrative industrialtree plantation projects (Diaz 1996). The idea is to develop about one millionhectares of land for tree plantations which would eventually supply therequirements of the wood-using industries and, at the same time, save some$ 500 million in foreign eXchange used to import the materials annually.
Based on a log supply-demand balance projections, the country's logrequirements will exceed supply up to the turn of the century. A few yearsthereafter, a positive balance is expected to be achieved resulting in oversupply of the material intended for processing.
Inter-Play of Favorable Factors
Some other influences could serve as indications of marketability ofstress-graded lumber. Looking back at the construction sector which is thebottom line of the marketing process, it is seen that opportunities appearendless. And one of the outstanding features of the Philippine society whichnowadays greatly influence the operations of the construction industry is theincrease in the average of income of Filipino families. It is this increase thatenables more families to actualize their demand for low-cost housing. In fact,the current construction boom is driven to a large extent by the vigorousdemand for socialized and low-cost housing. This leads to the conclusion ofindustry analysts that the rising per capita income along with growingconsumer confidence would sustain the growth in the property andconstruction sectors (Anon. 1997c).
Another factor going in favor of the application of stress-graded lumberin construction is the perceived receptivity to change of the intended market.Based from the exploratory field assessments of potential stress-gradedlumber consumers, a great majority expressed readiness to turn back at
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5.4. , .3
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tradition and not only buy the "new" product but even put additional money foracquisition of the material. It should be rioted, however, that thischaracteristic influence may be tied up to the generally improved earningcapacity of consumers' Nevertheless, the field study clearly shows thewillingness of consumers to pay even more for improved quality and reliability.
While favorable marketing factors do exist, still other influences canaffect demand for stress-graded lumber. The shift to non-wood building andhousing components is well underway. Steel has become a commonsubstitute for wood especially in trusses construction. Consumers claimready availability and cheaper price in the long run if steelis used. Stress-graded lumber can be made readily available if the market demands such.Lumber durability can be enhanced through chemical treatment and ste scan be undertaken to make the price more competitive with alternativematerials.
The culture, preferences and tastes of consumers have to be takeninto account also. Such attributes vary widely and may differ from person toperson, place to place and time to time. Wood offers natural beauty and allthe social, environmental and psychological appeal that goes with its usage.Whether these advantages can be translated into actual application remainsto be seen.
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5.4.2 Marketing Barriers Characterization
The rationale behind the intention to put stress~graded lumber in themarketplace is for a more judicious and intelligent application of wood inconstruction. The concept of stress-grading timber has been known for along time in more advanced countries and for some time in countries in SouthAmerica and Southeast Asia. Strangely enough, most if riot all of thesecountries do not implement stress grading and market do not exist for stress-graded timber. Reasons are varied but seemingly common to inaricountries. Some of these reasons are perceived to prevail similarly under thePhilippine setting.5.4.2.1 Culture/Tradition
At the time when log supply was still abundant, the mode of purchaseof lumber appeared simple as choice or preference was dictated commonlyby species. It was understood that a particular species provided the kind ofstrength or durability, color or even texture that rendered the wood suitable forspecific application in construction. Prices of the material were well withinreach of the common people. Most residential houses were of timberconstruction. With the sustained decline in timber resources starting the endof 1970's, a gradual change occurred in the construction habits of Filipinos.Steeltrusses, light metal frames and concrete floorings became commonplace. As wood supply continued to dwindle, the use of alternative materialgained acceptance to the point where house trusses which have been ofwood structure in the long past are now being replaced by steel. The
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combined effects of wood scarcity, price and convenience in the use of newmaterial have played significant roles in the transition.
The shift towards the popular use of stress-graded lumber will meananother venture which needs some cultural adjustments. The use of steeland other alternatives could become a status symbol, something which theFilipinos is fond of. Reverting back to timber, stress-graded at that, could betaken as non-status symbol.
5.4.2.2 Price Structure
The exploratory field assessments conducted to complement the pre-determined methodologies of this pre-project have shown the generalwillingness by some sectors to buy stress-graded lumber even for a higherprice than non-stress-graded material. Those concerned with reliability ofmaterials used in construction and whose professions are supposed toguarantee economical construction materials and methods, clamor for theimplementation of lumber stress grading. However, a number of respondentsin the potential consumers and traders group think otherwise. These peoplestressed that prices for stress-graded lumber should be affordable, moderateor made competitive with steel. Short of this, the search for alternative orequivalent materials will go on. Prices of other construction materials arealready high and minimizing construction cost is a prime concern.
5.4.2.3 Lack of Enabling Rules, Regulations, Policies or Laws
One of the perceived reasons why stress grading of lumber has riotprogressed in the Philippines is the absence of any system that covers itsimplementation. Without any agreement or understanding, nobody willventure into classification procedures especially when these entails additionaleffort, manpower, equipment and other support investments. There is nosense of going into stress grading when competing nori-stress-gradedmaterials are all around at perhaps lower costs and some, with the stamp ofthe Bureau of Products Standards. It will not matter much whether materialwastage results from over design of structures or difficulty is encountered inmaterial selection for specific applications. The path of least resistance andfaster turn over may always prevail.
5.4.2.4 Uncertain Supply of Stress-Graded Lumber
Granting that the consumer end recognizes the benefits of usingstress-graded lumber and pertinent laws or regulations have beenpromulgated forthe implementation of stress-grading, a sustained market forthe material may not be fully realized. The material should be readilyavailable. It is noted that in countries where stress grading rules exist, thereis difficulty in buying stress-graded lumber just because the material is riotavailable. This may sound unusual but it only emphasizes the urgency ofensuring production when demand is at hand. Continuous flow of materialsfor stress grading will need proper management and profitability of productionshould be maintained or enhanced. The absence or inadequate supply of
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stress-graded lumber will inevitably result in the shift to nori-woodalternatives.
5.4.2.5 Lack of Education and Promotion
Evidently the most significant marketing constraint is the lack ofawareness on the concepts and benefits of stress grading. Interestingfindings were obtained from the field assessments made in this pre- ro'eat.The term stress grading is generally known to most of the respondingpotential consumers consisting of engineers and architects butthe concept isunderstood by only 45%. About 35% gained their knowledge from textbooksand the National Structural Code for Buildings, about 5% from traininprograms and FPRDl publications, 15% from foreign references and about25% from industry publications. None of the respondents have used stress-graded lumber in their construction projects.
A review of the course content of leading schools in Civil Engineerin ,Architecture and Forest Products Engineering shows that lumber stressgrading is barely given emphasis in lectures and discussions in structuraldesign and wood utilization subjects. Students are introduced to the termonly when design stress values for calculations are selected from tablesfound in the National Structural Code for Buildings, however, the conce t isgenerally not understood.
All of the respondents representing the lumber traders sectors have nounderstanding of what stress grading is all about. They were aware of asystem of sorting lumber which involves simple visual inspection andclassification according to size; species and color are not important.Purchases are made based on size and perceived quality of wood. On theother hand, about 66% of the producers claimed to have knowledge of stressgrading but upon further investigation, their knowledge is limited toappearance grading.
If the results of the limited field study will be a reflection of a widersurvey coverage, and chances are good that it could be, then marketingdifficulty is certain to arise. It is unthinkable that buying and selling can takeplace for a commodity that is generally strange.
It is worthwhile to note, though, that after the concept was explained tothe respondents, 95 % of the consumers, and 70% of the producersexpressed their approval of the implementation of stress grading.
Considering that the major players in timber trade have but a very lowlevel of awareness on stress grading or even totally uninformed about theconcept, similarignorance could be expected from the common homeowners.Any marketing proposition, therefore, should strongly consider the educationand promotion aspects.
5.4.3 Entry Modes/Strategies
Having in mind the current wood supply situation, the controversysurrounding apparent sufficiency or nori-sufficiency of the material, the high
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prices of wood and availability of non-wood alternatives, the introduction ofthe concept of stress grading lumber could be a sensitive issue. End-userpreferences are not to be disregarded. The tendency to give premium totraditional wood species and particular colors may remain active. Propertiesof wood may be common but colors differ or the species have become sorare. Getting across the idea of stress grading, therefore will undoubtedlnecessitate a slow, calculating approach. A bit more sense, system, skill andtact will be valuable characteristics of the process. It is common thatintroduction of new concept or product is shrouded by constraints anddifficulties. A product can fail as a result of disoriented selling approaches orincomprehensive market assessments.
5.4.3.1 Linkages and Networking
The marketing process could start with the selection of the appropriateand logical entry points. Opening up of channels forthe transfer of the stressgrading rules concept will be directed to the key players in the product tradewho will influence, control, direct and implement the adoption of the idea andsubsequent marketing. Close relationships can be established with thepotential producers of stress-graded lumber such as the PWPA whichrepresents the interests of the country's sawmillers and other primary woodprocessing industries as well as the holders of Timber License Agreements(TLAs) and Industrial Forest Management Agreements (IFMAs).
Promotion of the stress grading procedures along with the advantagesand benefits of stress grading will also target the potential traders. Thissector serves as the sales conduit and market performance can be dictatedby the selling ability of the salesman. A good grasp of what is being sold, whyis it being sold and whatthe consumers get from the purchase will contributesignificantly to the viability of the business and ensure a successful marketinstrategy. It is unfortunate that, of the number of traders subjected to the fieldsurvey in this pre-project, not even one realizes what stress grading is.
Equally urgent is the need to interact with the would-be consumers ofthe stress-graded lumber. It has been noted that not a few engineers,architects or designers engaged in both big and small building contracts arenot aware of lumber stress grading. Marketing and consumer education havedirect correlation and market acceptance, enhancement and diversificationcan only happen if the end-users recognize the value of what is being sold.While efforts are to be exerted to encourage sustained production and viabletrading of stress graded lumber, operations of the producers and traders willlogically exist only ifthere is a market in realterms. The construction sectorin the Philippines is fairly well organized and good association can beestablished with such groups as the Chamber of Real Estate BuildersAssociation (CREBA), the Subdivision and Housing Developers Asscciation(SHDA), the Construction Industry Association of the Philippines (CIAP),United Architects of the Philippines, Philippines Institute of Civil Engineers(PICE) and Philippine Construction Association (PCA).
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The role of concerned government agencies need to be recognized.After all, these offices take charge of the over-all planning and exercisesupervision and control of and provide direction to the construction andhousing programs of the country. Specifically, the Housing and UrbanDevelopment Coordinating Council(HUDCC), The National Housing Authority(NHA) and the Bureau of Product Standards (Bps) will be vital participants tothe implementation of stress grading procedures and use of stress-gradelumber in construction. The HUDCC is mandated to formulate policies, goals,and strategies at the national level and to coordinate all housing programsundertaken by the various shelter agencies. The NHA, on the other hand, isthe main agency tasked with pushing the government's housing program forthe low and marginal-income sectors of society. A Committee on theAccreditation of Innovative Technologies (A1TECH) has been organized tomonitor new housing technologies and determine their structural reliability.Setting of standards and seeing to it that products conform to specificationsprior to marketing are responsibilities of the Bps.
5.4.3.2 Concept and Product Promotional Schemes
The exploratory field assessment showed one common sentiment onthe issue of why stress grading of lumber has never actually progressed inthe country. Poor awareness of stress grading or the total lack of it is claimedby the responding lumber producers, traders and consumers' Massiveeducation becomes evidently necessary. It seems clearthatthe problem isnot the concept of stress grading but rather on how the idea can becommunicated. Mode of dissemination can take various forms. Thoseconsidered practical in the local context will be described.
. Meetings, dialogues orotherinter-personals
Several studies on communications research show the very high levelof effectiveness of eye-to-eye contact when disseminating knowledge, ideas,principles or technologies. Careful methodologies have to be developed todetermine which party to meet first, what to meet on, desired output of themeeting or where to meet. The bottom line is that this approach providesbetter interactions and swift address to issues coining out of the subjectmatter.
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. MassMediaExposure
In terms of social and geographical coverage, mass media exposuresmay have the advantage. Several TV (specifically GMA 7, PT\/ 4, IBC 13,ABC 5 and ABS-CBN 2) and radio stations have timeslots for scientific andtechnological endeavor s which can be tapped either for personal interviewsor features releases. Press releases can be channeled to the major nationaldailies, e. g. , The Manila Bulletin, The Philippine Star, Philippine Journal, ThePhilippine Daily Inquirer, Manila Chronicle and Business World.
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* Technologyor Trade Fairs/Exhibits
Fairs and exhibits provide occasions for the expositions of newproducts, processes, concepts, breakthroughs or equipment. They can alsobecome interpersonal as there is opportunity for promoters to meetinterestedparties and discuss details of the commodity presented in the booth. Fairswhere the stress grading business will find relevance are the Housing andTechnology Fairs held normally towards the end of each year and the yearlyPhilConstruct Fair.
. Communications materialsproduction anddissemination
Reading materials can be produced fortransmittalto concerned partiesor serve as valuable support documents during meetings and dialogues, inmass media exposures and trade fairs or expositions. Communicationmaterials can take various forms or styles though emphasis should be onsimplicity and made straight forward but substantive enough to present thetopic at hand. The use of simple and easily understood language stands tobe appreciated better by both the producer and consumer ends. Thecommunication materials should create considerable appeal to readers.Production of a comics style promotional brochures or leaflets could be
effective to a large cross-section of Philippine society.
* Academic curriculum integration
Taking cognizance of the fact that many engineers, architects ordesigners in the construction business are short of knowledge in stressgrading, the inclusion of lumber stress grading principles along with theimpactthe system creates is something which can be explored. Educationand training programmes in three levels should be considered, namely,universitieswheF t dT'b ' 'universities where Forestry and Timber Engineering are offered, technicalschools and institutes where wood technology is offered, and industrialestablishments for wood products. To-date, curricula in civil engineering,architecture and related courses, forestry included, do not show significantconsideration on stress grading. The concept of stress grading is mentionedin passing, and the concept of strength groups is taken into consideration indesign calculations. If only to be consistent with existing developments andconcerns in the environment, the school curricula may need correspondingadjustments.
5.4.3.3 Product Entry/Marketing Channel
Marketing of stress-graded lumber could follow the sales path nowtaking place for ordinary ungraded lumber. Most probable sites for stressgrading are the lumber producers or sawmillers. Presently, lumber isdelivered to the traders which consist of big and smalllumber yards scatteredall overthe country. Big-time building contractors may procure the materialeither direct from sawmillers or from traders. Smaller constructions generally
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architecture and related courses, forestry included, do not show significantconsideration on stress grading. The concept of stress grading is mentionedin passing, and the concept of strength groups is taken into consideration indesign calculations. If only to be consistent with existing developments andconcerns in the environment, the school curricula may need correspondingadjustments.
5.4.3.3 Product Entry/Marketing Channel
Marketing of stress-graded lumber could follow the sales path nowtaking place for ordinary ungraded lumber. Most probable sites for stressgrading are the lumber producers or sawmillers. Presently, lumber isdelivered to the traders which consist of big and smalllumber yards scatteredall overthe country. Big-time building contractors may procure the materialeither direct from sawmillers or from traders. Smaller constructions generallyavail of lumber from lumberyards. Although stress grading may also beaccomplished at the trader's base of operations, the marketing flow basicallyremains the same except for some transactions between the lumberproducers and the traders both doing stress grading.
In the future, the market for graded lumber has the potential to expand.The secondary processing of graded lumber to produce components forprefabricated construction lends itself favorably to our government'sintensified drive to counteract the housing backlog. Mass production ofhouses with structural laminated lumber beams and columns, prefabricatedtimber components such as trusses, wall and floor systems is a possibility thatcan certainly not be discounted.
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5.5 IMPLICATIONSANDRECOMMENDATIONS
This study component of the pre-project took a look at the marketpotential of stress-graded timbers and proposed lines of actions so thatimplementation of stress grading and eventual marketing of product may berealized. It did not intend to create a concrete assurance of an immediateand ready acceptance of stress grading. Although done on a limited scale,meetings and contacts with various parties provided insights, views, opinionsand reactions which proved helpful in drawing up the following conclusions:
. A good prospect exists for the implementation of stress grading in thePhilippines. On the issue of whether stress grading should beimplemented in the country, there is an overwhelming positive reactionfrom individuals engaged in timber trade and construction. Some evencall for legislative means to putthe matter in motion.
. There are factors that will favor marketing of stress-graded timbers. ThePhilippines appear to the right policies and sound programs for asustained supply of wood forthe increasing population and the attitudes ofmarket participants are encouraging. Potential producers are ready and
70
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information dissemination is seen to have top priority and differentstrategies may be developed and applied to facilitate marketing.
. For stress-graded lumber, the flow of goods may be no different to existihgmarketing channel for recognizing the opportunities that exist for the localimplementation of stress grading.
The following points are suggested:
. Intensified promotions on the concept of stress grading are imperative toachieve the desired results. Introduction process needs to be slow so asnot to disrupt present practices. Transfer of knowledge may becomplemented by trainings designed for potential producers andengineers, architects or designers making up the consumer sector.Information need not be too technical but the extra money that theproducers stand to get and the worth of buying stress-graded lumbershould be articulated. Controlling government instrumentalities should bewell apprised of the timeliness of stress grading in order to addressproblems related to apparent scarcity of raw materials, emergence ofhighly mixed species in the market, importation of mixed and unidentifiedspecies and environmental implications.
. See how the rest of the marketing barriers can be overcome. Forexample, pricing for stress-graded lumber should be carefully studied toachieve a highly competitive footing in relation to non-wood alternatives.Legislative back up on the other hand should be taken with extremecaution. The timber industry claims that there are already a good numberof laws and policies directed to their operations.
. Management of transition sensitivities deserves prompt attention. Art andskill are necessary in dealing with the total process, from introduction ofthe concept down to final implementation of stress grading and marketingof stress-graded lumber. Sensitive areas include culture, product cost andbusiness profitability.
The appropriate entry modes or marketing strategies should be wiselychosen. Identification is to be made as to which system or systems will bemost effective in bringing positive results.
In order to actualize the implementation of stress grading in thePhilippines, attempts should be made to formulate a full-scale,comprehensive project that will address the conclusions andrecommendations presented in this initial study. The local implementation ofstress grading and popular market acceptance of stress-graded lumber are toform the goals and aspirations of the future project.
,I
.
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Chapter 7
CONCLUSIONSAND RECOMMENDATIONS
The timber industry in the Philippines is experiencing the effects ofstrong competition and the extensive loss of some of. its markets becausewood has not been developed as an engineering material to the same extentas steel, reinforced concrete and aluminum.
Like those in most tropical countries, the Philippine forests arecharacterized by a great variety of timber species of which relatively few arecommercially utilized. These few species have been over exploited that theremaining virgin timber stands are now located in remote hinterlands makinglogging operations and transport quite expensive. Much valuable timber hasalready been lost not because of ignorance on the value of wood but more forlack of efficient system whereby such timber could be profitably utilized. Ifonly timber utilization could be rationalized and lessenknown species bemade available for suitable end-uses, then the timber supply situation wouldappear promising for forest conservators, timber producers and consumersalike.
This study examined the feasibility of developing and implementing alumber stress grading system in the Philippines in order to conserve ourdiminishing forest resources through efficient utilization.
On the technical aspect, prerequisites of an effective stress gradingsystem such as visual grading rules, strength groups and stress grades havebeen incorporated in the National Structural Code of the Philippines. Thesehave been recognized by Civil/Structural Engineers in their designcalculations since 1972, however, the absence of stress graded lumbermakes it impossible forthese engineering tables to serve their purpose. Thebasic allowable stresses of timber species for construction are constantlbeing updated and these are published regularly in the FPRDI Trade Bulletinseries. Methods of equivalencing the strength of defect-free timber with thatof structural sizes must be devised and this entails extensive testing of thespecies mix used for construction. Once equivalencing models have beenverified, the reliability of stress grading machines can be monitored.
Considering the current species mix available in the market, a systemwith a reliable stress grading machine and with allowance for visual overrideis appropriate forthe current mixed species supply in the Philippines. Machinestress grading is an adjunct to visual stress grading, and one method can notsubstitute forthe other. A species independent stress grading- machine must
72
,
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,
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~
be developed and the conceptinitially worked out by FPRDl researchers canserve as a starting point in its development.
The mixed tropical species resource in the Philippines does not lenditself to conventional processing and marketing channels. There areLKS/LUS species which have very small volumes that evaluation of propertiescannot be justified. It would be economicalIy favorable ifthe machine can befabricated locally so that costs can be kept as low as possible. The reliabilityof this machine must be monitored constantly and the parameters reviewedregularly in each shipload of lumber.
The future of lumber stress grading depends on its being introduced inindustry in a responsible manner and on proper control and inspection ofmachines by independent authorities. Its successful implementation requiresthat stress grading not be limited to research, but should be integrated in theproduction process as soon as, and consumers, having realized the benefitsof stress grading, should clamor for engineered structures using qualityassured lumber. The ultimate aim of the timber industry should be thedevelopment of an efficient and economical stress grading and handlingprocess from seasoning to dispatch on the one hand and the provision of fulldesign data for stress graded timber on the other.
The adoption of strength groups and the acceptance of design valuesin the NSCP by design engineers must be complemented by strict monitorinprocedures by building officials. However, inspection of lumber that is alreadyin place but without any stamp as to which quality standard the productadheres, practically makes post inspection a futile activity. Hence, theConstruction Industry of the Philippines (CIAP) must work hand in hand withthe FPRDl to obtain the sanction of the Bureau of Products Standards (Bps)on stress graded lumber. Inspection and monitoring must also be conductedin the sawmills. The Department of Trade and Industry (DTl), which issuesbusiness licenses, must coordinate with the Philippine Wood ProductsAssociation(PWPA), to discuss possible incentives for stress graded lumberproducers and traders. Government bureaus involved in construction,specially those on the housing segment such as the NHA and HUDCC,should spearhead the promotion of quality assured lumber by specifyingstress graded lumber in all government projects, and should encourage,through A1TECH, innovative construction technologies on stress radedlumber. CIAP also has mandate on the private construction sector and canimplement training programs on stress grading through the PhilippineDomestic Construction Board, the body that accredits building contractors.
Based on the foregoing historical and projected data and information,we can foresee a lumber supply deficit until year 2015. To overcome this,more massive establishment of tree plantations should be encouraged and anincrease in the volume of log importations have to be resorted. The utilizationof these species is an incentive to plantation owners/tree farmers as they willhave ready for their produce. Moreover, the current volume of lumberavailable in the market is still significant, thus, stress grading is warranted asthis will redound to more efficient and scientific wood utilization thereblessening the pressure on the remaining timber stand.
J
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Stress-graded lumber must be perceived by both producers andconsumers as having value. That additional value must be translated in termsof a higher price for stress graded lumber that consumers must be willing topay for. The target market should accept it and there must be ability andwillingness to pay on the part of industry and consumers' Cultivating demandfor stress graded lumber starts with informing the target market of what stressgrading is all about and what it can do for them. If demand does riotmaterialize and there is no perceived and actual value added, then a pricedifferential between stress graded and non-stress graded lumber will not exist,and no economic incentives can be derived from stress grading.
The benefits of stress grading lumber for structural use can be realizedunder assumptions of product acceptability and market demand. For projectimplementors, the initial task should aim at eliminating information and culturalbarriers that stand in the way of its adoption and use.
For potential investors like sawmill operators and lumber traders,determining the economic viability of a stress grading operation will involve adeeper examination of the market, cashflow projections and activities aimedat creating demand and achieving sustainability.
Based on the marketing analysis, a good prospect exists for theimplementation of stress grading in the Philippines. On the issue of whetherstress grading should be implemented in the country, there is anoverwhelming positive reaction from individuals engaged in timber trade andconstruction. Some even call for legislative means to put the matter inmotion.
The Philippines has the right policies and sound programs for asustained supply of wood for the increasing population and the attitudes ofmarket participants are encouraging. Potential producers are ready andwilling to turn out stress-graded lumber if market does exist while traders willsimply adjust according to market demands. More importantly, theconsumers will adoptthe product realizing its practicality, and economic andenvironmental implications. Also, the construction boom is real. For masshousing alone, the gap between supply and demand continue to widen on ayear-to-year basis.
Intensified promotions on the concept of stress grading are imperativeto achieve the desired results. Introduction process needs to be reasonablylow so as not to disrupt present practices. Transfer of knowledge may becomplemented by trainings designed for potential producers and engineers,architects or designers making up the consumer sector.
Information need not be too technical but the extra money that theproducers stand to get and the worth of buying stress-graded lumber shouldbe articulated. Controlling government instrumentalities should be wellapprised of the timeliness of stress grading in order to address problemsrelated to apparent scarcity of raw materials, emergence of highly mixedspecies in the market, importation of mixed and unidentified species andenvironmental implications.
:.
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Pricing for stress-graded lumber should be carefully studied to achievea highly competitive footing in relation to nori-wood alternatives. Legislativeback up on the other hand should be taken with extreme caution. The timberindustry claims that there are already a good number of laws and policiesdirected to their operations.
Management of transition sensitivities deserves prompt attention. Artand skill are necessary in dealing with the total process, from introduction ofthe concept down to final implementation of stress grading and marketing ofstress-graded lumber. Sensitive areas include culture, product cost andbusinessrof'tb'I't 'business profitability.
The appropriate entry modes or marketing strategies should be wiselychosen. Identification is to be made as to which system or systems will bemost effective in bringing positive results.
In order to actualize the implementation of stress grading in thePhilippines, attempts should be made to formulate a full-scale, comprehensiveproject that will address the conclusions and recommendations presented inthis initial study. The local implementation of stress grading and popularmarket acceptance of stress-graded lumber should be the focus of the futureproject. Figure 17 shows the targeted outputs of the future project,categorized into the three major aspects that need to be addressed as pointedout in this pre-project study, namely technical, economic and marketingstudies, and training and information dissemination. Each component will behandled by a working group headed by a national expert. The figure alsoshows the organizational/sectorallinkages that each working group willinteract with untilthe implementation of the technology. Figure 18 presents aflowchart of the proposed major activities of the future project. As aconcluding activity, a regional workshop will be held in order to demonstratehow the grading rules and implementation mechanism developed in the
Philippines can serve as a model for introducing stress graded timber intoother tropical timber producing countries.
.,
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DEVELOPMENTAND IMPLEMENTATION OF LUMBER STRESSGRADING RULES FOR TROPICAL TIMBER IN THE PHILIPPINES
o
o
TECHNICAL
Stress grading systemDesign manual/
Tropical timberengineering handbooKIncorporation of stressgrading rules in theNSCP
*
ECONOMICS andMARKETING
n
*
*
*
MPWHNHA
HUDCC
Price structure
Marketing programIncorporatestandard on stress
graded lumber inthe nationallyrecognizedmaterials standard
AsEP
Figure 17
TRAINING andINFORMATIONDISSEMINATION
BpsAND
BOl(DTl)
* Training programsfor producers,traders, andconstructors
* Information
dissemination
Target outputs and organizational linkages of the threecomponents of the future project on the development andimplementation of lumber stress grading rules in thePhilippines
PWPA
PREPAREDEISGNMANUAUHANDBOOK
DEVELOPSTRESSGRADINGSYSTEM
CREBASHDA
DETERMINEPRICESTRUCTURE
PREPARESTRESSGRADINGCODE
CIAP
PRCPICEUAP
Figure 18
PREPAREMKTG
PROGRAM
PREPARETRAININGPROGRAM
INCORPORATEIN NSCP
PREPARESTANDARDFOR SGLUMBER
CONDUCT INFODISSEMINATIONPROGRAMS
Flowchart of activities of proposed project on thedevelopment and implementation of lumber stressgrading rules in the Philippines
CONDUCTTRAININGPROGRAMS
INCORPORATEIN BpsSTANDARDS
CONDUCTREGIONALWORKSHOP
76
C
,
BSI 1991. BS 5268 Part 2. British standard structural use of timber: code ofpractice for permissible stress design, materials and workmanship.Brit. Stand. Inst. , London.
Burger, L. G. Den. 1923. De gronskagen voor de classificate van Ned-Iridische Timmer Loutsoorten. Techora DL. 602-607.
Burgess, H. V. 1956. Strength grouping of Malaysian timbers. Ma. For.19(I). Forest Department, Kuala Lumpur,
Collins, M. J. and Hj. Mohd. Amfn Ashaari. 1990. Investigation of machinegrading of Malaysian hardwoods. Proceedings of the 1990International Timber Engineering Conference held on October 23-25 inTokyo. Volume 3. p 827-833.
DAP-DENR. 1989. Policy study on wood supply and demand. Quezon City.Philippines.
DENR. 1990. Philippine Master Plan for Forestry Development. Quezon City.Philippines.
Diaz, C. 1996. EDC looking for $ I B to finance tree plantations. ThePhilippine Star 28 October 1996.
Dupaya, D. A. 1997. UHLP: Shift to a multi-window lending system. Housingand Technology Fair 1997 Souvenir program, Housing and UrbanDevelopment Coordinating Council(HUDCC).
Eastin, I. L. 1996. Marketing strategies to promote sustainable forestmanagement in tropical Africa. FPRDI Jour. 22(,) Jan. -Jun. : 79-88.
EDM. 1991. Tropical Timber in Construction and Development of HarmonizedStress Grading Rules. ITTO pre-projectreport. Yokohama. Japan.
Engku, A. R. 1972. Basic and grade stresses for strength groups ofMalaysian timbers. Malaysian Forester 35(2).
ESPiloy, E. B. Jr. 1976a. Stress grading of structural sawn lumber. FPRlTech. Note No. 161.
t.
ESPiloy, E. B. Jr. . 1976b How working stresses of Philippine Timber arederived. FPRI Tech. Note No. 170.
ESPiloy, E. B. Jr. 1977. Strength grouping of Philippine timber species forstructural purposes. NSTA Tech. Jour. V01. 2-4.
ESPiloy, E. B. Jr. and Siopongco, J. 0. 1978 Basic stresses of Philippinewoods I. FORPRIDE Digest, V01. 7 No. 2&3, pp. 37-40.
ESPiloy, E. B. Jr. 1981. Recommended working stresses for visually stressgraded Philippine timber species. FORPRIDE Digest, V01. 10, No. 1-2.
78
ESPiloy, E. B. Jr. 1984. Simplified sets of working stresses of timberthrou hstrength grouping system. FPRI Journal, v01. 12, No. I Jan. -March.
ESPiloy, E. B. Jr. 1988 Strength properties of coconut sawn lumber andpoles. Chapter 4. Coconut wood utilization research anddevelopment. The Philippine experience. By Forest ProductsResearch and Development Institute and IDRC, Canada.
Eurofortech. 1995. Timber Engineering STEP I. Basis of desi n, materialproperties, structural components and joints. First Edition. HJ Blass, PAune, BS Choo, R. Gorlacher, DR Groffiths, BO Hilson, P. Racher, G.Steck(Eds) ' ' ' ,
Fewell, A. R. 1984. Timber stress grading machines, BRE Information a erIP 17/84.
Forest Mangement Bureau. 1996. Philippine Forestry Statistics. QuezonCity. Philippines.
FPR01. 1998. Proceedings of the FPRDl - Industry Dialo ue andPlanning Workshop. 15-16 April 1998. Los Banos, Laguna.
FPRDl and ITT0. 1998. Compendium on low-cost houses from smalldiameter logs, thinnings, tops and branches. IsBN 971-626-004-0.S. K. S. Lopez (Ed. ) 107 p.
Indonesia. 1974. Methods used in the testing and classificationtimbers. Working paper presented to ASEAN technical meetingforestry in Kuala Lumpur. July 1974.
FORPRIDECOM. 1980. Guidelines forthe improved utilization and marketinof tropical wood species. Prepared for FAO by Forest ProductsResearch and Development Commission (FORPRIDECOM) College,Laguna, Philippines. Contract No. RP/GH 1979/FO.
International Rice Research Institute. 1991. Basic procedures forAgroeconomic Research. Los Banos. Laguna.
Kamasudirdja, S. 1979. Suato pendekatan daian perhitunganyang diperkenankan untok bebe papa kelas tegangan kayu.the Committee of the Revision of PKKl, Indonesia.
Khaidzir, 0. M. 1998. Personal communicationto FP Soriano from FRIM,Malaysia.
Lauricio, F. M. , A. N. Rainos and J. 0. Siopongc0. 1970. Workin stressesfor stress graded lumber of Philippine structural species. PAENCOR17(4).
Leicester, R. H. 1981. The future of grading structural timber. Proceed in s ofthe XVlllUFRO World Congress. p35-46.
I'
FPRl
R & D
of
on
teganganReport to
79
Leicester, R. H. 1984 Structural grading systems. Pacific Timber EngineerinConference, Auckland, New Zealand.
Leicester, R. H. 1985. Proof Grading Technique. Proceedin s of theConference on Forest products Research International- Achievementsand the Future held on 11-16 April 1985 in Pretoria. Volume 4.
Leicester, R. H. 1988. Timber Engineering Standards for Tropical Countries.Proceeding of 1988 International Conference of Timber En ineers.Seattle, Vol. I For. Prod. Res. SOC. , Madison, Wisconsin, pp. 177-85.
Leicester, R. H. , H. 0. Bretinger and H. F. Fordham. 1996a. HarmonisedStandards for Evaluating Bending Strength. Proceedings of theInternational Wood Engineering Conference held on 28-31 October1996 in New Oneans, Louisiana, USA. Volume 2. GOPu, V. K. A. (Ed).Omnipress, Madison, W!.
Leicester, R. H. , H. 0. Bretinger and H. F. Fordham. 1996b. A coin ansonof in-grade test procedures. Proceedings of the International Wood.Engineering Conference held on 28-31 October 1996 in New Orleans,Louisiana, USA. Volume 2. GOPu, V. K. A. (Ed). Omnipress, Madison,Wl. '
Groinala, D. S. 1996. Machine Graded Lumber: Questions and Answers. InAutomated Builder September issue. p 22-24.
Leciester, R. H. and C. A. Seath. 1996. Application of Microwave Scannersfor Stress Grading. Proceedings of the International Wood EngineerinConference held on 28-31 October 1996 in New Oneans, Louisiana,USA. Volume2. GOPu, V. K. A. (Ed). Omnipress, Madison, Wl. '
Leicester, R. H. 1998. Personal communication to FP Soriano dated 18October 1998.
Madsen, B. 1975. Strength values for wood and limit states desi n.Civil. Engineering. 2(3), 270-9.
Madsen, B. (1978). In grade testing problem analysis. For. Prod. J. 28(4),42-50. '
.
Madsen, B. (1984). A design code for contemporary timber engineering andits implications for international timber trade. Proceeding of PacificTimber Engineering Conference, Auckland, May 1984. V01. 3, pp. 950-71 .
Mateo, R. F. 1998. Personal communication to FP Sonano regardin the costof fabricating an electro~mechanicalIy operated lumber stress gradinmachine
MCTimpeny, S. 1998. Personal communication to FPproduct proposal on Metriguard 7200 CLT-I.
Can. J.
Soriano regarding
80
Manila, A. 1998. Resource availability of lessenused species. Paperpresented during the Appreciation Seminar on the Utilization of Lesser-
Used Species. 30 April1998. Los Banos, Laguna. Philippines
Mettem, C. J. 1981. The principles involved in stress grading with specialreference to its application in developing countries. Report preparedfor the Experts Group on Timber Stress Grading and StrengthGrouping held on 14n7 December 1981 in Vienna, Austria
Mettem, C. J. 1982. Problems and some suggestions in the identification ofappropriate stress grading techniques for developing countries. Reportprepared forthe Experts Group on Timber Stress Grading and StrengthGrouping held on 14-17 December 1981 in Vienna, Austria
Metriguard. 1992. Precision Testing Equipment for Wood. Catalog 20-1. 53P.
L
Morrison, Hershfield, Burgess and Higgins (MHBH), Limited. 1981. DraftReport on The Training and Inspection Programmes for QualityAssurance of Stress Graded Structural Wood Products. Prepared forthe Meeting on Timber Stress Grading and Strength Grouping on 14-17December 1981. United Nation a Industrial development Organization.Vienna, Austria.
MTIB. 1989. The Malaysian grading rules for Sawn Hardwood Timber. 1984edition. Malaysian Timber Industry Board, Kuala Lumpur, Indonesia.
Muller, P. H. 1966. Mechanical stress-grading developments in Europe, NorthAmerica and Australia, with proposed research programme ommechanical stress grading in South Africa. Special report submitted tothe Timber Unit Steering Committee, WNNR/CSIR. Pretoria, SouthAfrica. 45p.
NSCP. 1992. Wood, Building Tower, and other Vertical Structures. Chapter3, National Structural Code of the Philippines, V01. I, 4'' ed. Pp. 47-71.
Philippine Forestry Statistics. 1996. Department of Environment andNatural resources. Manila. Philippines.
Philippine Wood Products Association. 1996. Annual report. Makati Cit .Philippines.
Philippine Wood Products Association. 1998. Personal communicationswith the PWPA Executive Director Leonardo Angeles. Makati City.Philippines.
Rahman, E. A. 1971. Basic and Grade Stresses for Some MalaysianTimbers. Malayan Forester 35(2) Forestry department, Kuala Lumpur.Malaysian Forest Trade Service Trade Leaflet No. 37. MalaysianTimber Industry Board. Second Edition.
81
Sono, P. 1974. Merchantable Timber of Thailand. Symposium on Researchand Marketing of South-East Asian Timbers and Timber Products,
organized by the German Foundation for International Development(Berlin) and the Government of the Republic of the Philippines, Manilaand Los Banos, Philippines.
SAA. 1986a. As 28858: Timbersoftwood-visually stress-graded forstructural purposes. Standard Association of Australia, Sydney.
SAA. 1986b. As2875: Timber-classification-into strength groups. StandardAssociation of Australia, Sydney
Soriano, F. P. 1986. A report on low-cost housing in the rural area. Technicalreport on the survey conducted in selected areas in Luzon from 25 Julyto I August 1986. FPRDI Library. Los Banos, Laguna.
Sunley, J. G. 1968. Grade stresses for structural timber. For. Prod. Res.Bull. 47, HMSO. London.
Sudokusumo, S. 4987. Developing a stress grading system for houseconstruction in Indonesia. Presented at the First Conference CIB-W18B Tropical and Hardwood Timber Structure, Singapore.
Tahir, Hilmi Md. , Mohd. Shukari Midori, Chu Yue Pun, Nor Azian Mohd.Kasby and Roszalli Mohd. 1996. Handbook of Structural TimberDesign: Simple Solid Members. FR!M Technical InformationHandbook No. 6. Forest Research Institute Malaysia. Kepong, 52/09Kuala Lumpur. 147 p.
Tamolang, F. B. , E. B. ESPiloy and A. R. F10resca. 1995. Strength Groupingof Philippine Timbers for Various Uses. FPRDI Trade Bulletin Series 4.ISSN 0117-4045. FPRDl, College, Laguna. 31p.
TRADA. 1974. Visual grading of timber. Explanation and prooficialinterpretation of visual grading elements of BS 4978: 1973 - Timbergrades for structural use. Timber Research and DevelopmentAssociation, High Wycombe, England.
TRADA. 1997a. Structural use of hardwoods. Wood Information. TRADATechnology Section I Sheet 17.
TRADA. 1997b. European strength classes and strength grading. WoodInformation. TRADA Technology Section 4 Sheet 21.
Tebbe, J. 1987. Investigation of the national and international standard ofmachine stress grading. Proceedings of the EEC Seminar on Woodtechnology, Munich.
Vinopal, G. W. 1985. Grading and Testing Machines Developed at (NationalTimber Research Institute (NTRl), CSIR, Pretoria. Proceedings of the
,
82
Conference on Forest Products Research International- Achievementsand the Future. Volume 4. pp 3-16.
Walker, J. C. F. 1993. Grading timber, Primary wood processing principlesand practice. Chapman and Hall, London, p. 321-376.
Webster, F. E. 1993. Defining the new marketing concept. MarketingManagement 2(4): 23-31.
UNIDO and TRADA. 1984. Stress Grading Rules for Tropical Hardwoodsand Conifers. 31 p.
UsDA. 1987. Wood Handbook. Wood as an Engineering material. UsDAForest Service, Agricukture Handbook No. 72.
UsDA. 1990. American softwood standard. PS-20-70. Us Dept. Coinm. ,Washington, DC.
Zusman, Pinhas. 196 A theoretical Basis for determining Grading andSorting Schemes.
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APPENDIX I
Questionnaire for producers and traders
"
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84
, PPD 12/96/byin 14
DEVELOPMENTANDIMPLEMENTATIONOFSTRESSGRADINGRULESFOR
TROPICALTIMBlERS
Name:
Name of Organization:
Address:
Tellfax/email:
PARTA. STRESS GRADING: AWARENESSANDIMPLEMENTATION
The questions below aim to assess the existing level of understanding on stress gradingamong lumber producers and traders. It attempts to derive views and opinions regarding theimplementation of stress grading rules in the Philippines.
I. Awarenesso"StressGradingofLumber
I. Are you awareofsortinglumberbystressgrading?Yes No
OccupatioiVPosition:
a. Please state what you 1<now about stress grading
b. Please state what you know about Visual Stress Grading
c. Please state what you know about Machine Stress Grading
2. Are you aware of the benefits of lumberstress grading?Ifyes, please enumerate/explain
No
3. How did you come to know about stress grading? Please identify source of infonnationCodes/StandardsTextbooks
Foreign referencesTrainingIndustry Publications others, please specify
4. Do you know of any company that produces stress graded lumber?
Philippines
Abroad
11.
No
Implementation of Lumber Stress Grading Rules
I. Should lumberstress grading rules be implemented in the Philippines? Yes NoIfyes, please give four (4) recommendations on how lumber stress grading rules may beimplemented in the Philippines (e. g. intensified information campaign, generalagreements, policy/legislative action, etc. )
Yes, please identifyNo
Yes, please identify
a
b.
C.
d.
Ifno, why?
2. In your opinion, why has lumberstress grading not been implemented in the Philippines?(Please state in order of importance)
3. Do you want stress grading rules for lumber to be implemented in the Philippines?Yes
Ifno, why?
4. Ifyou were required to stress grade lumber, what would be your minimum acceptablereturn on investment? %
5. Will you be willing to invest in a stress grading equipment?Yes
Ifno, why?
6. Given the benefits of consumer satisfaction, do you think consumers/end-users will bewilling to buy stress graded lumber at a higher price?
2
7. Please give some additional thoughts on the market potential of stress graded timber forconstruction purposes in the Philippinesa. Local use
b. Export
8. Do you wish to receive more information aboutlumberstress grading?Yes No
PARTB. PRODUCTPROCUREMENTANDSORTINGSYSTEM
This part of the questionnaire deals with current procurement and marketing practices ofyour company. These information will help us assess the existing environment to which stressgrading will be introduced.
I. Product Procurement/Source
Please indicate the sources, volume bought and buying prices of your product by species.,
SpeciesSawlogs
Source
Remarks:
Lumber
Volume bought per month
Sawlogs Lumber
Buying Prices
Sawlogs Lumber
3
I
11. Sorting/Grading System
I. . How are these products sorted/graded?
by speciesby colorby sizeby densityby moisture contentby defectsOthers, please specify
2. Based on the above sorting/grading system, please indicate market outlet, volume sold,and selling prices.
Sawlogs
,
Species Market Outlet
Lumber
Remarks:
Volume Sold
3. Whatisthepercentageofyourlumberrejects? %
4. Please state reasons for rejecting lumber
Selling Price
5. How many workers do you employ for sorting/grading?Wage rateVolume per 8 hourshift
4
6. Do you haveanyspecialtrainingonsorting/grading?Yes NoHow much is the cost of training?
7. What problems do you encounter in your present system of sorting/grading?
8. Please give some suggestions on how these problems may be solved.
PARTC. COMMENTS
.
The Project Team wishes to express its sincere thanks for your cooperation in accomplishing thisquestionnaire.
5
APPENDIX 2
Questionnaire for consumers and end-users
.
,
85
PPD 12196jbrm IB
DEVELOPMENTANDIMPLEMENTATIONOFSTRESSCRADINGRl. ILESFOR
TROPICALTIMBERS
Name
Name of OrganizationAddress
Tellfax/email
I. UTILIZATION OFLl. IMBERINCONSTRUCTION
I. Do you use lumber in your construction projects? YesIfyes, proceed to 2;ifno, proceed to 5.
2. In whattypes of structures have you used lumber? Please provide infonnation for at leastone (1) project in each type.
A. Vertical structures
I. Commercial building
Occupation/Position
,
Name of ProjectLocation
Project costYear completed
Lumber LISed ::
a. fonnworks/
scaffoldingsb. beams
c. posts/studs
e. platesf. mouldings
cabinetsg.h. others
No
d. door/wdwjambs
Vol
(bdft. )cost/
bdft.
ii. Residential
Name of ProjectLocation
species
Project costYear completed
source
Lumber used:
a. formworl<SI
scaffoldingsb. beams
c. posts/studsd. door/wdwjambse. platesf. mouldings
cabinetsg.h. others
Vol
(bdft. )cost/
bdft.
,
iii. Others; specifyName of ProjectLocation
species
Project costYear completed
Lumber used:
source
a. fomiworks/
scaffoldingsb. beams
c. posts/studsd. door/wdwjambse. platesf. mouldings
cabinetsg.h. others
Vol
(ban. )cost/
bdft.
B. Horizontal structures
i. Roads and highways
species
Name of ProjectLocation
Project costYear completed
source
2
Lumber used:
a. formworks/
scaffoldingsb. others
Vol
(ban. )
ii. BridgesName of ProjectLocation
Project cost
cost/
bdft
Year completed
Lumber used:
a. formworks/
scaffoldingsb. others
,
species
Vol
(bdft. )
iii. Others; specifyName of ProjectLocation
source
Project cost
cost/
bdft.
Year completed
Lumber used:
a. forrnworks/
scaffoldingsb. others
species
3. Were you satisfied with the quality of lumber delivered at the construction site?Yes Reason
Proceed to 4.No
4. a. Reason for not being satisfied with quality of lumber delivered?
Vol
(bdft. )
source
cost/
bdft.
b. What percentage of lumber delivered did not meetthe required quality?c. Haveyou everrejected sub-standard lumber delivered at the site?Yes No
species source
3
Ifyes, was the supplier willing to replace rejected lumber with good quality lumber?Yes No
Ifno, what was your course of action?
Please proceed to part H
5. Please state reason for not using lumber in construction projects.
Please proceed to part 11.
11. AWARENESS OFSTRESSGRADEDLUMBER
I. Are you awareofsortinglumberbystressgrading? Yes No (Proceed to5)a. Please state what you know about stress grading
,
b. Please state what you know about Visual Stress Grading
c. Please state what you know about Machine Stress Grading
2. How did you come to know about stress grading? Please identify source of informationCodes/StandardsTextbooks
Training Foreign referencesIndustry Publications others, please specify
3. Haveyouusedstress-graded lumber manyofyourprojects?Yes NoIfyes, please state name of project and other details below:
Name of projectType of structureSource of lumber
Quantity of lumber usedSpecific use of lumberCost of lumber per bd. ft.Year completedOther infonnation
Ifno, lease state reason/s for not usin stress raded lumber
4
4. Do you know of any company that produces stress graded lumber?
Philippines Yes, please identify
No
5. Are you aware of the benefits that can be derived from using stress graded lumber?Ifyes, please specify
Abroad
No
6. Are you awareofanymeansofsorting/grading lumber?Yes Noa. Ifyes, please describe.
No
Yes, please identify
b. Is the existing system of sorting/grading of lumber adequate for your purposes?Yes
Ifno, why?
,
7. Are you aware of the provisions on wood utilization in construction in the NationalStructuralCodeofthePhilippines?Yes NoIfyes, do you find them useful in your job?
Ifnot, why?
111. IMPLEMENTATION OFLl. IMBERSTRESS GRADING RULES
I. Should lumberstress grading rules be implemented in the Philippines?Yes NoIfyes, please give four (4) recommendations on how lumber stress grading rules may beimplemented in the Philippines (e. g. intensified infomiation campaign, generalagreements, policy/legislative action, etc. )a.
b.
C.
d.
Ifno, why?
5
2. In your opinion, why has lumberstress grading not been implemented in the Philippines?
3. Given the benefits of consumer satisfaction, are you willing to buy stress-graded lumber atahigherprice? Ifyes, by what percent are you willing to pay more for stress gradedlumber?
Ifno, why?
4. Do you agree that the use of stress-graded lumber in construction should be mandatory bylegislation?Yes, state reason
Ifno, state reason
,
5. Please give some additional thoughts on the market potential of stress graded timber forconstruction purposes in the Philippines
a. Local use
,
b. Export
5. Do you wishto receive more information aboutlumberstress grading?Yes No
IV. COMMENTS
The Projectteam wishes to express its sincere thanks for your cooperation in accomplishing thisquestionnaire
6
APPENDIX 3
Information brochure on lumber stress grading
L MBER S RES
Koi orig@n @ to?
ORAD^N
^I
I""
<
.
86
APPENDIX4
Program of the FPRDl-ITTO Consultative Workshop on Lumber StressGrading held on 29 July 1998 at the Forest Products Research and
Development Institute
.,:,:'. ..,., .u*?, ,
ONSULTATIVE WORKSHOP^^". T, !I^;,,*;:,FEAs, .B, LITY OF Lullj^ER-SfR;ESS '."."
-;:" .*" GinD^"G ," THE PHI;LIP, ^,"E$.,. L. F " ..,.. ,".,. ',
."..,,. ....",.*, F , . ~ . '
,\
,
I
. . . ,~.,.~.
.+. ,..
'.:'-9<9 - ,
'., 'V. ' ," .:L ,...
. .. $. v, - ,
5:<,I
"'S. " - " ' "', ' -' "" I"""".",,.;:*. = ! ' " "'.. ." , .-.. ..,.,,.
,
EAR
,, ' '*..,
R DUCERS
CONSTRUCTIORIDUSTRY
GoSE To
^!!;>
EDU ATORS
*.",",',\' *.. ..,- ',."' "" ,'
*'-,.^;-;*--: ::,^'^^I^Dr. Ifii@- pPD ,. 27^6^'.-*'t{ '-,',^t-': -,',^Z^I^IZE"Z(^'Ii'/!^^/^':AiV^"'in?'PLEA!^A^'?4717@Ai~.@^"';"-..:;;11. .- }*:e;^sinE;5'3. 6'1^1402iy!<;';RU4^:/;^^R I^-\'*',. !*:'.,<,*,'. *t, ', ',.',--. ' ""*c' . ' "'.",* - A, . ..,, I*-,.' ,.*..*\. y" """ "**'it"" "',*,* .,. . ~' ' 11' '~ '. I " "" I " ,=.';. **,'*".
';;:, I;Orest:^i'6d"in=I^^!^esedrd. " "~b^y 16 ' ' '*, ^"',,?'-'*.-'.- ,:<,, .*-, *., :- '.*- - UpLB (^611^^Ie, 'lostBatidS\ I^g'14rj^,--^"> .I - ".-!^". .-~ ,.* , .""
, .~ . .*,"*.,... ,.. * ,. ~- , ,,,*!> ~. . ... ,.. .,:,-.&.,-:. ",.,*,. ~ . :'. , .. * .,. .,
us
APPENDIX 5
Participants of the FPRDl-ITTO Consultative Workshop on LumberStress Grading with the ITTO PPD, 296 Project Staff
and newspaper article on the pre-project study
I4.4
,^, 4- 94^ ^;!^*
Top(L-R) Mr. F. by (Maple Resources), Dr. F. Mauricio (Farmer), Dr. V. Feinandez Mar, UpLB), Dr. E. Rainiiez (A1TECH), Dr. J. Stopongco(AsEP). Dr. E. Bello (FPRDl), Dr. W. Ametica (InO PPD 1296 Asst Leader), Ergr. L. Maimy (PANELCORP), Engr. E. ESPiloy. Jr. (pro^Clstain, and Mr. S. DUGay (SHDAjBottom (L-R): Mr. C. Camo (project slam. Dir. Diaz (ERDB), Dr. I. Pabuayon Innjecl consultant), For. Cadiz (FMB. DENR), Engr. J. Sese(DPWH). Ms. C. Garcia(project stain. Dr. F. Sofano (projectleader), Arch. C. Tychuaco (NHA). Emu. W. Hosefia (project research asst), EngrF. Moredo (project stain. Mr. M. Ahaide (Provident Tree Farms) and Engr. R. Rondero (project slam
#
Sti'ess gi!'adii!. g systom. foil Innl, et'-in RF ^^'^!I^.donorthe^clot. ': , .' ~':Asderi^CStr^581^gsystemforlum^rin ^re^b^nteraidy^ladUr^^r
the Philippines used in sumeru"ICOirsmiction is nines ton SEE^ ^ such asbtodu^s, re- - -GBjznds. unu, dyadeinthemmirryfuou^I310"pre^and"^,^n^^p. ~. use^ing"orkedoutbyat^10f^urinent"" I- ^digs, ed^or^u^,. WELLty, ,axi^,.SIM^edu^"^'a^^t"^'^hI^cbe:3.11reForestP^as^hand mulatto"^^^"din^^I
'D^!Dongirfo&inure, nagacyofdieDe^tcall"chasm^g^gad' ^3.10. or^^camLTha^^^horn European cointties damg ^k lo'. t^^yofSdaiceandTechnolngy .. intosBati0;83^. moridrs, "^I"^..1900, . I'*:'43-Onceinphce, thesis wildanble!^IPIo- Dr. Fin^^^,:die^^"^the
eBBisane, ^mar^^yal^t^^kducetstocb"nilumberproductsaccording to re^IQnl, ^mr^"g^^s timid to^I^ado^v^.^.sumgrh values atxi Is^mm a, xi maya^ hdp an be imphm^^'tide MPP^. ^lit^corb . qssqseoflqm^'in!h^ceofd^ling Ekedine, ,xi a^"Icom^^Fin^ * ~ " .'
supply. : ':-"- '.';, firstbeir, p via'productaccepabiliry, tie--up rip^*wire^.' .. 9:^'corsMostpmd^sun^Lyra, onvts^tsi^n 'I^^^, icyg, I'm^"xip
I^!^"'gadum se^q, '.'^;;^n^i, - ^,innre^areof sadadsuas^s^anal of dyingIha^^.'"are"I^commasaidupnp. onlywidilumba' 'Mainlinetha^mmg coL^^^duniatforsttumualt^buts^gnuetim^, s^is^0^rfora^couch"10thatom, ^
Dr. So^loader. Phi^^rigortha^isI^I;FFRDl's^lire^1st, - I^^e^^^001adtha^Caterfor
trite^aAgimlrumlRe^^all^^ringO. ;,,^^,,^,^'cf!hThe introduction ofsu^ Inn^is a-peadroamew, "6.9"., in^icyof, ^'p^
11^for^using 511 Sei^^bulbings^OS, tile^^. The pro^Crdubbed 'Manu^cone of 10, <03, .rin^"Ism4^!qdie!calc^B^:by. ^^.^e"cot:coqpo!"^, us!,$p .'.'^"" fr^j, P'"' ,^^an^. re^, Dai' ^"' Re"^"Ithes^^g^rentsajdnt
projecrofFProlaruldieLi^ITro^I^F.~
r, !* -J
THE PHIUPPiNEsrAR
*$i"
I^'Or^^n^inlay"L
12", ^21. ,. 21 I^:?f'
\
35
88
APPENDIX 6
UNIDO Simplified stress grading rules fortropical hardwoods
----.----------------------------------------
.
.
----------------------~---------- -
.
.
.
.
TYPE LieDEFECT
------------------------------
.
.
.
.
Slope oEgratn
.
.
1-1AXl;-iUi-I '15/4tilSSLULi: DERE:C'Is FOR EACH Gi<ADB
:Interlocked s
.
.
' '3raLn
.
.
.
...-- - .. .
.
.
.
.
.
.
jinOLS-
SLrucLural No. I
.
.
s Limiting: dinensioii
.
.
L
.
.
.
.
.
.
.
.
.
I in 16
,
,
.
.
210ngitudtnal: Only one knot allowed perseparation : ,netre oE length.
.
: One eLghth of the thickness gone quarter o6 the allckness gor width to which it is or width to wiltch IC is
: related Up to a Inaxiinum OE g related Up to a nexti:Irun Of38 in dialtei:I^r. 75 Inn dial!ECer.
11n 6
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
s Fissures- :
.
.
-- -- .-^.----..--.---
.
.
Structural No. 2
.
.
.
.
, .shallow*g Etssures
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
, Moderate*Eissures
I in 11
.
.
.
.
.
.
.
.
.
.
.
s Not to exceed one sixt. :t oEtile tiltckness
.
.
11n 4
Large* Permitted only ab the endsg fissures and: and limited as above.splits
7~^--.-- -
: Resin gone resin gockeL, width ijob gone resin 130ckeb, ,,'dth :: LockeLs : greater Litaii6 fun, LengUi : greater titan 10 lain, I C' s: : 110.1rorebliaii50iiTn, :riotirr>LetiianLhewidLh. E :: : every metret)Cpiece. = tilesliece, ever 600.1. E :' : :L. ;IeoieceorcoiibinaLtoi. ~g: goesiiialleconesoEsimilarg.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
gallovred per netre oE length. s
.
.
Onlyone sizeableknoL g
g;, here L:vo or itore knots are s
.
.
.
.
sseparal:ed lengthwise by less s:than twice die width oE thegpiece, the sum oE tile knobssshall be checked against bile s
limiting diiTension.
----
.
.
.
.
ilone
.
.
.
.
.
.
..
.
.
.
.
..
------------------
.
.
.
None
.
.
.
.
.
.
.
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.
.
.
.
.
.
.
.
.
.
111 length, riot Co exceed0.2 CLIres Lhe width, orI. 5 Lines the IenJU, ,
whichever is the lesser.
Permitted
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
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.
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.
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.
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.
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.
.
.
.
.
.
.
89
^-^^-^^-^^^^^-^^^^
.
.
=Distortion- s..
s Spring..
.
.
.
.
Twls^
.
.
.
.
,.
.
.
.
.
.
.
.
.
Cup
.
.
,.
3.5 Inn In 2 in length
g Trisect
Bow
.
.
s hales-
.
.
.
.
.
.
s Pin holes s 16 pithol. es in a s^uare of s 32 pinholes in a square oE s100 inn sides 100 rim sides
.
.
.
.
.
.
.
.
gsmL holes 82 in a square of 100 inn sides 24 in a square of 100 rim sidesss and grubs holes
\
none
.
.
.
.
.
.
.
None
.
"
,
SLarge borer =
.
.
.
.
= holes
.
.
None
.
.
.
.
7 mm in 2 in length
I mm per 25 rim of widthin any 2 in length
g I rim per 25 Inn of width
.
.
.
.
.
.
.
.
.
.
.
.
^-.^^,-
:Bark pry:ketsggand includede
Wane
.
.
.
.
.
.
.
.
.
.
s PIiLoein s
.
.
-----
.
.
s 1.16 the sum of width andthickness
s 15 Inn per 2 in length
.
.
.
.
.
.
.
.
.
.
.
.
.
None
: Stain free sfrom decay =
.+^----a
.
.
.
.
.
.
.
.
.
.
.
.
.
.
s Other
.
.
.
.
2.3eEects- g..
.
.
.
.
.
.
.
.
.
.
.
.
none
SCOirpression sfailures
.
.
.
.
g
.
.
.
.
.
.
E~2 holes of 6 inn dia. Flax. s
.
.
= Tension
Bin a square of'100 Inn sides, s
.
.
g wood
.
.
.
.
.
.
.
. ^.
e 1.14 the sum of width ariathickness
.
.
spungal decays
Permitted
.
.
.
.
.
,-
.
.
.
.
28rittlelieartg
s The length oE bark pockets ss and strands or included
gphloem intersec!:In-g the ends s: of a piece shalL riot exceed s
die width of the piece.gElsewhere not to exceed 1.5 'sstines tile width of the piece. s
--..----------+
.
.
.
.
.
.
.
.
.
.
.
.
.
.
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.
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..
Boxed
heart..
140rle
.
.
.
.
.
.
--------------
.
.
.
.
.
None
.
.
.
.
.
.
-----+
.
.
s Not permitted in basic saviii sizes where either thetiltckness is a^ual to, or less than 100 inn or the
s wtdUi is equal to or less than 225 rin.
.
.
None
.
.
.
.
.
.
.
.
.
.
none
Permitted
..
.
.
.
---^-^..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
^^.
.
.
None
.
.
.
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.
.
None
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.
None
.
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.
.
None
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.
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.
-.--------
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,.
.
.
90
-----------------------------=-------------^..
APPENDIX 7
UNIDO grade ratios for structural no. Iand 2 for hardwoods
.
.
.
.
.
.
.
.
^
.
.
.
.
g Bending..
PROPBl^Ex
s nodulus of elasticity
s Tension
.
.
.
.
g Congression parallel
e CollpreSSion perper^ICUlaZ
"
.
.
,
.
.
g Shear...
------~-------------
* of bending, I. e. , 0.60 x 0.80 - Structural No. I grade0.60 x 0.67 - Structural No. 2 grade
.
.
.
.
.
' Structural' N6. I..
*
.
.
RATLO
s 0.80 I
.
.
.
g 1.00
or
' 'Structural' No. 2
.
.
s 0.60
.
.
.
.
.
s 0.90,
.
.
.
.
.
.
s 0.83
.
.
.
.
.
.
.
.
s 0.83
o. 67 I
.
.
I
.
.
.
.
.
.
,.-4.4
.
.
.
.
0.95
.
.
.
.
.
.
.
.
O. 60I "
...~ -
.
.
.
.
.
.
.
.
0.88
.
.
.
.
.
.
.
.
0.75 I
.
.
.
.
O. 67
../ 8
.
.
.
.
.
.
.
.
.
.
91
APPENDIX 8
Limits of defects by grade in joists andplanks for seasoned wood (NSCP 1972)
KIND Or burnCIS
A. NA'runAi, liprnci's
I. Worm holes, averagedinmEICr (Inarin, ,, Inall, ,w"I, Ie size in mm)a. 1.1divi, 1.1"I
b. Quantity limitstion
2. Slope or Grain (Makimi, invari"lion in n, in Irom longi.11, dinal nuts per 300 mmwill, ill middle hall of ICngih)
3. Check and Shakesa. Size o1 each check antl
shake, or it in combin, -lion, Ithe SI, in rillhe 9:7. CSor all checks antl shakeswilljin nthldle natf ,, rdenii, or 1/1e piece SIIallriot exceed:
,I
SIress Grade80%
:,
,
b. rind pellet raiion: Checks'11/11 spliis at Ihe rillddle11niior Ihe demih or Ihe11iece shall, ,o1 e"lend a 1/4 1/4 3/8distance greaier Ih"n: o11hickness or Ihickness of Ihlckness
Knots (Mn, jinum allowable size N, rrow Along Narrow Along Narrow Alongo1 individual kiloiin rinm') raceon center raceon tenler faceon center
edgeof lineo, edgeof linenr edge01 line01Noniiiialwidiliof lace, in nin, . wide wide wide wide wide widerare face lace race race lacewllhln wiihin will11nIhe middle Inc middle Ihe rilld, IleIhir, I or Ihird or Ihlrd oflength Iengil, lengthof piece or piece or piece
182538506070809095
100
Nol permiiiedNol permiiied
SIress Grade63%
18
2Nol cl"SICred
Stress Gradeso%
1/461th ick"egg
25
6Nol clustered
1/4of Ihick"CSS
so75
1/1012515/121/11250311015114/10
450 rill, 1.1ver
32
1/1e, cm, ,"1111e. 1.1e, ,,,.", 11nw, ,a. ", I 1.1 I .R in'y ' rime. ,E pnPo, ,, n. Ie, Ironr".trial. Tb, ,.".,,."Inn, inn, in. h. 11n, ,bean *11 h , '' ''m. ,in, ,mr. ,,.. 1.1, .I, .,Brioiip, ,11.11 rini Ile penmliie, .
3/8or Ihlckness
6121825303518454RSriSri
B. 11ANDLING, MANUFACTURE ORPROCESSING DFTEcrsI. Wane (maximum allowable
si7e in mm)Nominal race dimension in mm
18253038So55657075
so75100I 25ISO200250300350400450 and over
2. Torn grain (allowable deplhin inni)
3. Skip, , allowable si, erini 10 exceed: SI, rince area(widlh nim x ICngih)Denih nimOuanjily
1218253045so55657075
75
3038so608090
100100100
38so6075
100110125125
3366
1012Is18202530
100 125
121215Is202225283845so
2
widih x 100
Is kip per 5in or shorter
ICngih
1212IsIs20253038455055
2
width x 1002
I skip per Sin or shorter
length
3
width x 1003
I skip perSin or shorter
ICngih92
I.
S ecies(Common anIbotanicalnames)
High Strength Group
L^, sin I an::^^'^;If;,; '^fun:';;\I',,,,,,^ac^!^,^';:;^;^':I;'rt^,.)Nari^( anco spp. ),::^, 11, ^11!^its inariniodendron ahemianum (Merr) Bakh. I
B!,\^:t IX:;^jig;^;If^;; excelsum (Blume) Miq. IDao (Draconjori!CIOn SIP')Ga!, san^Careinia VCnu OSa (Blanco) Choisyl
Kama^, g 1,111hrophloeum densinorum (Elm. ) Merr. lKato (Amo0rasppj 'Loinarau (Swimtonia foxworthyi Elm. )Mahoga. ny, Big-IQafed ($wintonia macrophylla King)Makaasim (Sys{18ium rillidum Beqth)Fahuian (Mangi^re spp. )
APPENDIX 9
Recommended working stresses forsome Philippine. ;timber (NSCP 1992)
11. Moderately High Strength Group
(1)
"
..
Bending andtension
parallel togrann
"
,
lispP to abbreviation or, peeie. (Flur. I). Thi. mean. 10r crimple, ,hat M. lab. y. ba. to conpo. ed or more Ih. n one , eele. . See the lint at end orTable 3.1.Source: Philippine Timber DC. 18n Standard. (I. E. Roc. fort and 1.0. Slopongco) November. 1991 (FFRDITerminal Repor, )
(2)
Modulus or
elasticity inbending
MPa
80% Stress Grade
26.325.028.725.824.021.831.324.5
Compressionparallel to
grain
(3)
1000MPa
111. Medium Strength Group
B^Ii{^^'tP^;:^^::;^^:ai^:h%nan in c MDongkalan (Calophyll"in spp. )Gisau (Can arium spp. )La::"\;^'gy' IGOnystylus macrophyjjum (Miq. ) Airy ShawlMum. ^^" ^^^^"^",, 3 '
Nat0 41a$, uipmspp. )pine (^i"us ^PP. ) . .Salakin (Aphanamixis spp. )Vidallanutan IHibiscus campylosiphoii Turcz.
var. 81abrccens (Har. ex. Perk. )l
IV. Moderately Low Strength Group
Bayok6'Iero^!;ermumspp, ) .,,R;^j:^j^^!;11n:':^'::!,'R^'82Merr. l ~
8.229368.309.636.548.339.72978
CompressionPC endicular
o grain
(4)
18.618.918.116.220.821.820.919.018.818.419.816.520.518.918.016.6
MPa
(1)
14.515.615.816.015.413.721.615.8
(5)
Shearparallel to
grain
5.356576.365.436.848477.207.566.828.047.924.666.726.665.946.53
MPa
5.914.318.706.036.344.97
10.26.27
(6)
10.811.411.39.44
13.513.211.711.211.910.611.810.511.411.211.410.0
MPa
2.952.643.022.782.882.613.382.49
3.903.273.412.273.524.264.393.954.843.462.983.833702.323.072.50
(2)
MPa
2.062.242.181.922.362.402.472.352.291.962.182.712.402.141912.05
(3)
16.516.616.314.315.013.913.816.815.415.716.213814.7157
19.5
1000MPa
(4)
7.316.486.385.336.065.835.415.946.306.505.565.986.66567
5.83
MPa
(5)
9.56 '9.899.208.168.968.188.549.519.338.839.178388.298.83
8.54
MPa
11.812.613.212.811.912.6
(6)
2.202.332.481.992.021721.962.923.072.782.332.731.882.94
2.65
MPa
5.474.754.135.362754.09
1.731.821.981.901.841.481.591.852.072.061.981.681.561.88
2.39
6.277.336.857.467.237.87
1.441302.001.973.32340
.
1.471.201.661.442.071.96
93
S ecies
(Common ant!bolanical names)
I. 11ighStrengthGroup
",'I:^^^;;:;;^^^;:^;;;''^I, :::;\Ij, .lMalabayabas (Tristania spp^^1:1;^,^ac^if;^I (;I^^j:;;Prt, ,.)^::;^f ^;;^^:^^hl, damnon "her"ian"in (M",,) Bath. IYakal( horea spp. )
Bin gas Grininaliaspp.
Dao (Draconion!elOn SIP"Galasan Ga, cini" ren"^sa (Blanco) ChoisylGuijo (S orea. spp. )
Kama^:Ig 17th!ophloeum densinorum (Elm. ) Merr. IKatb (Amo0ra spp^ 'Loinarau (Swintonia toworihyi Elm. )Mahogany, Big-Iealed ($wintonia macrophylla King)Mainkauayan 1/1"c"SOCa, pus hilippinensis (Forw. ) 00 La"b. lFahuian (Mangi{era spp. )
(1)
11. Moderately 11igh Strength Group
,
.
Bending andtension
parallel tograin
Modulus ofelasiiciiy in
bending
(7)
MPa
63% Stress Grade
Compressionparallel to
grain
(8)
20.719.722.620.318.917.224.719.3
1000MPa
111. Medium Strength Group
Compressionperpendicular
lograin
(9)
^'';'f' ' ^,^,:;^;:;!^:atg^^onan (Blanco) Merr. IDangkalan (Calophyll"in spp. )Gisau (Can an urn spp. )hanulan-bagyo IGOnysiylus lilacrophylluni (Miq. ) Airy ShawlLauan (Shorea s^p. )Malaanonan (S^orcas p. )
^;It^^!{;:^:^^^:;;^s -Miau f^>ysoxylum sp, .,Nato ala^:Iiumspp. )Palosa^. is (^. nisopicra spp )Pine (^i""s spp. ) . .Salakin (Aphanamixis spp. )Vidallanuian 1/1ibiscus campylosiphon Turcz.
var. 81abrecens (Har. ex. Perk. )l
Almaci a IAgathis dammara (Lamb. ) Rich. l
,ay" , "'^^!;:;!'!u^c::^j^owjjMerr. )Manggasinoro(ShoreaSPPj rr.Raintree Samanea saman ( at^.) Merr. IYemane IGmelina arborea R. ^r. )
6.477.376.537.585.156.567.657.70
MPa
14.714.914.312.816.417.116.615.014.814.515.613.016.114.914.213.1
(1)
(10)
11.412.312.512.612.110.817.012.0
Shear
parallel to
Mra
4.215.175.014285.396.675.675.955.376.336.243.675.295.244685.15
rain
(11)
4.653.396.854.755.003.928.074.94
IV. Moderately Low Sirengih Group
MPa
8.538.98890743
10610.4
9.218.799.388.349.308.248.958798.977.88
2.322.082.382.192.272.062.671.96
3.072.572.681.792.773.353.463.113.812.732343.012.921.832.421.97
(7)
Mra
(8)
1621.771.721.511.861.891.951.851.801.541.712.131891.691.511.61
13.013.112.811.211.810.910913.312.112.312.710.91/612.4
15.4
1000Mra
(9)
5.765.105.034.204.774.594.264.684.965.124.384.715.244.47
4.59
MPa
(10)
I
7.537.797.246.437.066.446.727.497.356.967.226606.536.96
673
MPa
9.26994
10.410.09.379.90
(10)
1731841.961561.591.351.542.302.422.191.842.151.482.32
2.09
MPa
4.303.743.254.222. 163.22
1.361.431.561.491.451.171.251.461.631.621.561.331.23148
1.88
4.945.785.395.87570620
1.131.031581552.612.68
./
1.160.951.311.141.631.55
S ecies
(Common an Ibotanical names)
I. HighstrengthGroup
j^I:^;^^^;;:;;^^^;;^;;;';^^un;;\Iiq. lMalabayabas (Tristania spp^^;:1';;^^^!!;:!;^;^:,;'It;,,Nan^({anco spp. )Sasa^I I^eijsmanniodendron ahemianum (Merr) Bakh. lYakal( borea spp. )
B" 1" 3"Dao (D, acontqm. 10n SIP"Ga!asan 10arcinia venul;sa (Blanco) ChoisylGuno (S orca. spp. )
K:^;:f:;I. I^;g^;^^:^^Idensinorum (Elm. ) Merr. IKaio (Amo0ra spp3 'Loinarau (Swintonia foxworihyi Elm. )Mahogany, Big-leafed (Swintonia macrophylla King)
Malaka"ayan Inccusocarp"s hilippinensis (row. ) de La"b. lFahutan (Mangl^era spp. )
(1)
11. Moderately High Strength Group
,
Bending andtension
parallel torain
(12)
Modulus orelasticity in
bending
Mra
50% Stress Grade
Compressionparallel to
grain
(13)
16.415.617916.115.013.619.615.3
1000MPa
1/1. Medium Strength Group
Compressionper endicular
o grain
(14)
B!'I^!';'n'I^I^;:It';:='!'::a^:^h^nan (Blanco) Me, r.Dangkalan (Calophyllum spp. )Gisau (Can arium spp. )Unutan-bag, o IGOnystylus macrophyllum (Miq. ) Airy ShawlLauan (Shorea s p. )Malaanonan (SIoreas p. )
M:It;^^'{I^0^;1'^':;;^'N;;: ^'a{;"'1 'rn sp, .Palos\!lis ( nisoptera spp. )Pine ({I"us ,pp. ) . .Salakin (Aphanamixis spp. )Vidallanutan IHibiscus camp 10siphon Turcz.var. 81abrecens 01ar. ex. Per^.)l
Almaci a IAgaihis dammara (Lamb. ) Rilh. I
""^;:"'"!':"^c^;;:owii Merr)Man^gsinoro (Shorea spp. )Rain^tee Samanea saman (Iac .) Merr. IYemane IGmelina arborea R. ^I. )
5.145855.196.024.095206.083.11
MPa
11.611.811.310.113.013.613.111.911.711.512410.312.811.811.210.4
(1)
(15)
9.069.769.90
10.09.608.5913.59.55
Shear
parallel to
MPa
3.344.113.973.394.275.304.504.724.265.024952.914.204.163.714.08
rain
(16)
3.692.695.443773.963.116.40392
IV. Moderately Low Strength Group
Mra
6.777.137.065.908.428.227.316987446.627.386.547.106.987.126.25
1.841.651.891.741.801.632.121.55
2.442.042.131.422.202.662.742.473.032.172.862.392.311.451.921.56
(12)
Mra
1291.401.361.201.471.501.541.471.431.231.361.691.501.341.201.28
(13)
10.310410.28.939.398.688.63
1059.629.80
10.18.659.199.83
12.2
1000Mra
(14)
4.574.053.993.333793.643.383.713.944.063.483.734/63.54
3.64
I
Mra
..
(15)
5.976.185755.105.605.115.345.955.835.525.735.245.185.52
5.34
MPa
7.357.898277.987.437.86
(16)
1.371.461.551.241.261.071231.831.921.741.461.701.181.84
1.66
MPa
3.422972.583.351.722.55
1.081.141.241.181.150.930.991.161.301.291.241.050.981.18
1.50
3.924.584284.664.524.92
I
0.900.811.251.232.072.13
0.920.751.040.901.301.23
I. Malabayabas (Tristania spp. ) includes:
Malaba abas (T. decoriicaia Merr. )Tiga (t!'microntha Metr. )
Dalingdingan (H, roworthyi Elm. )Man gachapui(11. acuminaia Merr. )Yaki^-sapl"rigan 111. PIagata (Blanco) Vid. I
^:;;^,(}I^:1:1^^^"t^^;^!^;;^;i^.^I':;;^^", ha, .o
Yakal (S. ast 10sa Foxw. )Yakal-gisok Is. isok POW. )Yakal. in abolo j^. cillata Kiri^)Yakal-in alibato (S. maiibaio^)oxw. )
^:;'^il';^^: :!:I;^31^;:;^ Merr. IKubi(A. nilida Tree. s p nilida)Nangka (A. heterophy^a Lain. )
Binggas IT. cit, in a (Gaertn) Roxb. IUni au (I'. copelandii Elm. )Saka{(T. nilens Fresl. ) .Taiisai-gubat (T. roetidissima Grill. )
Dao ID. dan (Binn"0) Me, ,. & Roll"lminio ID, .d"to (Blanco) Ske. Is. I
2. Manggachapui(Hopea spp. ) includes:
3. Nang (Vatica spp. ) includes:
4. Yakal (Shorea spp. ) includes:
S. Antipolo (Arthocarpus spp. ) includes:
6. Binggas (Terminalia spp. ) includes:
I
7. Dao (Dracontomelon spp. ) includes:
,
8. Guno (Shorea spp. ) includes:
Gui'o Is. guiso (Blanco) BlumelMa^guno (S. piagaia Foxw. )
""""i;'In^?f;:lit;"^^:!rt, ,,^::;^::;^"^if;::;i^::;ion'. IKaimon (D. philj incnsis RottenKatmon-bayani .megalaniha err. )Malakatmon ID. uzoniensis (Vid. ) Marrellil
Kato (A. ahemiana Merr. )Katong-Iakihan (A. macrocarpa Merr. )
Fahuian (M. allissima Blanco)Fahong-11iian (M. nierrillii Mukh. )
^pito"g, ^,, I %, co- '^"^""^^j;;;^'^randis)Ma^apanau (b. kerrii Kiri );:^;:^':a^!:;If;;^^.^!:idatus Fo .)
9. Kamagong (Diospyros spp. ) includes:
14. Dangkalan (Callophyll"in spp. ) incl"des:
Dangkalan ^:. obliquinervium Merr. )Bitaog (C. Inophyll"in L. )
Dulii C. hirsuiuni Willd. forma multipinnaium,. (L anus) IIJ. Lainl
Gisau (C. vrieseanun, En I. )
;^^:;'11/1^:I^'^I^;^^i:;^!^11'1^I^')^:.'^;ayi
Lauan, ^6d (S. negrosensis Fo .)I, auan, While is. contorta Vid.^:{;^;',!^';,^;:;;^^:I^I;;^,, y^1,1, ,,Kal"nii[S. hopeifolia (Ileim. ) Sym. ]Malaanonang (S. poliia Vid. )
110-ilotA. iloito(Binn, 0)Me, ,^, . ,,,. b 'Malasaging (A. diffusa Merr. )
Malugai Iy. pinnaia ForSI. )Malugai- iitan (P. pinnata forma responda Iacobs)
15. Gisau (Can an urn spp. ) includes:
10. Kaimon (Dillenia spp. ) includes:
16. Lauan (Shorea spp. ) includes:
11. Kato (Am o0ra spp. ) includes:
12. Fahutan (Mangilera spp. ) includes:
17. Malaanonang (Shorea spp. ) includes:
13. Apiiong (Dipierocarpus spp. ) includes:
18. Malasaging (Aglaia spp. ) includes:
19. Malugai (Pometia spp. ) includes:
20. Miau (Dyso!cylum spp. ) includes:
Kulin -babui(0, allissisum Merr. )Miau ^D. euphle^ium Merr. )
Malak-malak IP. philipp. rise (Perr. ) C. B Rob. lNato IP. I""oni. nets (F. -Vill. ^Vid. IPalak-palak (Planceolai"in ^laneo)
Afu (A. brunnea Foxw. )Dagang (A. aurea Foxw. )
Pine, Ben^uet (P. kesiya RO IC ex. Gordon)Pine, Min^oro (F'. merk"sii{ungti & de Vr. )
Kan ko (A. perrotieiiana A. juss)Sala^in IA. c"mingiana (C. be. )l
Bayok IP. dinersifolium Bl"me)I
Manggasinoro Is. assamica Dyer. forma
Man 'a;i^^;::'^'i^;i^:^ I^)v{:mens Pan's)
21. Nato (Palaquium spp. ) includes:
22. Palosapis (An isopiera spp. ) includes:
23. Pine (Pinus spp. ) includes:
^.
24. Salakin (Aphanamixis spp. ) includes:
25. Bayok (PIGrospernium spp. ) includes:
26. Manggasinoro (Shorea spp. ) includes:
APPENDIX 10
Minimum strength group limits for groupingPhilippine timber species (NSCP 1992)
Pro ert
MOR (MPa)
MOE (1000 MPA)
Moisture
Content
MCS (MPa)
Green
12%
,
CP (MPa)
Green
12%
G,
SH (MPa)
78.5
122.6
SIren th
Green
12%
SG (Abstract)
G2
12.7
I5.7
Green
12%
rou
61.8
98.1
of Timber
G3
39.2
63.7
Green
12%
9.81
11.8
49
78.5
8.83
13.2
G4
Green
12%
29.9
49
7.52
9.32
39.2
61.8
9.81
13.7
5.49
8.83
G5
23
378
5.88
7.16
309
49
0.67
0.71
7.85
10.69
3.48
5.69
18.1
29.4
4.51
5.49
0545
0.58
6.19
8.34
2.21
3.68
I3.7
226
0.45
0475
4.9
6.37
1.37
2.4
0365
0385
3.92
4.9
03
0315
94
APPENDIX 11Recommended end used for
five strength groups of Philippine timber(Tamolang et. at ., 995)STRENGTH GROUP
Class I(High Strength)
.
For heavy duty construction where bothstrength and durability are required such as inship building, railway sleepers, friction andhearing blocks, pulley sheaves and rollers,bridge and wharf timber, telephone andtelegraph poles, mine timbers, posts, high-grade beams, girders, rafters, chords andpurlins, window sills, balustrades, treads,stairs and highway railway railguards, salt andfreshwater pilings, vehicle spokes and frames,and dumb bells.
For medium-heavy construction such as heavy-duty furniture and cabinets, mediumLgradebeams, girders, rafters, chords and purlins,flooring, door panels and frames, pavingblocks, boot and shoe lasts, bobbins, spindlesand SIIuttles, howling pins, pickersticks,sailboat parts, gunstocks, tool handles, wheelshafts and axles, cant hooks and peavies,parquetry, veneer and plywood face, studs forcar and truck bodies, airplane construction,sporting equipment like baseball bats,checkerboards 'and golf clubs, tripods, T-squares and kitchen implements like mortarsand pestles
F()r medium c()nstructi()n such as generalframing, panelling, medium-grade furniture andcabinet, veneer and plywood face and core,low-grade beams, girders, rafters, chords andpurlins, interior trimmings, panelling andflooring of cars, radio and stereo cabinets,bodies of musical instruments, cases forinstruments and jewelries, drafting tables, dug-out boats, dry measures, mill products, felloesand C()(IPerageS.
For the producti(In of pulp and paper, woodcarving and sculpture, conventional furniture,drafting boards, toys, venetian blinds, crates,pallets, form wood, shingles and matchwoods.
For light construction-where strength, hardnessand durability are not critical requirementssuch as mouldings, ^"ash, door and panel cores,ceiling and acoustic panels, pulp andpapermaking, wall boards, pencil SIats,matchsticks, popsicle sticks and ice-creamspoons, core veneer, fans, wooden shoes, cigarboxes, buoys and floats.
Class U (ModeratelyHigh Strength)
END-USES
Class 1/1 (Medium Strength)
Class IV (ModeratelyLow Strength)
Class V (Low Strength)
95
ITTO PPD 1296 PROJECT STAFF
Pre-project leaderAsst. pre-project leaderResearch Assistant
Technical Review
Demand and Supply
: Dr. F10rence Pascua-Sonano: Dr. Wilfredo M. America
: Engr. Wency B. Hosefia
: Engr. Enrique B. ESPiloy, Jr.Engr. Thomas Rolan E. Rondero
: Dr. Wilfredo M. AmericaMr. Claro R. Cantio
: Ms. Carolyn Marie C. Garcia
: Engr. Felix C. Moredo
: Dr. Isabelita M. Pabuayon
Economics and Finance
Marketing
Consultant
96