The Role of LCA in Green BuildingDesign and Assessment:

Focusing on True EnvironmentalPerformance Measures

Wood Products Council and the Wood Solutions Fair is a Registered Providerwith The American Institute of Architects Continuing Education Systems. Creditearned on completion of this program will be reported to CES Records for AIAmembers. Certificates of Completion for non-AIA members are available onrequest.

This program is registered with the AIA/CES for continuing professionaleducation. As such, it does not include content that may be deemed orconstrued to be an approval or endorsement by the AIA of any material ofconstruction or any method or manner of handling, using, distributing, or dealingin any material or product. Questions related to specific materials, methods,and services will be addressed at the conclusion of this presentation.

Program Education Credit Information

Learning Objectives

• The why, what and how of Life CycleAssessment (LCA)

• The LCA toolkit• The integration of LCA in rating systems• The near term approach of assembly

assessment and ranking• The freely available EcoCalculator for

assemblies

Materials and resources creditsare especially weak in rating

systems . . .

. . . and very controversial

No! It’s aboutcertification! It’s all about

renewability!

Actually, you’re both wrong . . .

The use of wood is a good example

Materials selection is all about trade-offs!

CO2 neutral

Harvesting issues

Low energy

Abundant resources

Locally available

Recycled content

Water pollution

High CO2

Resistant to pests

regional

recycled content

rapidrenewability

durability

By attribute?

or...

Weighing material options

By environmental performance LCA

Resourcedepletion

Acid raindamage

Water pollution

Climatechange

Air pollution

Life CycleLife CycleAssessmentAssessment

transportationtransportationenergy useenergy use

emissions to airemissions to air emissions to wateremissions to water

solid wastessolid wastes

resourceresourceextractionextraction

effectseffects

resourceresourceuseuse

(depletion)(depletion)

water usewater use

A methodology for assessing the environmentalA methodology for assessing the environmentalperformance of a product over its full life cycleperformance of a product over its full life cycle

The ISO 14040 Framework

Life Cycle Assessment Framework

Goal & ScopeDefinition

InterpretationInventoryAnalysis

ImpactAssessment

Direct Applications

•Product Development& Improvement

•Strategic planning

•Public policy making

•Marketing

•Other

LCA in Relation toBuildings

Tracking Flows: The Inventory Step

BUILDING CONSTRUCTION(manufacturing)

OCCUPANCY(use, reuse, maintenance)

DEMOLITION/DISPOSAL

MATERIAL ACQUISITION

Manufacturing

Products / Assemblies

EnergyEnergy

WaterWater

MaterialMaterialresourcesresources

EmissionsEmissionsto:to:

AirAir

WaterWater

LandLand

Raw Material Acquisition

Waste Management

Recycle / Reuse

Products / Materials

Impact Assessment PhaseInventoryInventory

Impact Assessment Impact Assessment (Valuation)THE GOAL: to measure ultimate impactson human and ecosystem health

Impact IndicatorsImpact Indicators(characterization

& Normalization)

• fossil fuel depletion• global warming potential• ozone depletion• ground level ozone (smog)• acid rain• toxic releasesair/water/land• etc.

The rest of the story isthe energy to make andmove energy — calledpre-combustion in LCA

End use energyestimates just one

part of the story

Even sourceenergy doesn’t

get it all

In the Case of Energy…

LCA Limitations

LCA is not the answer to all problemsLCA is not the answer to all problems

E.g., does not readily handle such issues as:

Indoor environmental quality• Improved ability to deal with air quality possible in future

Uncertainty and risk related to toxic releases

Site specific resource extraction effects

The Uncertainty Factor

Occurs over aOccurs over arelatively shortrelatively short

time frametime frame(e.g 18-36(e.g 18-36months)months)

Is likely to lastIs likely to lastmany yearsmany years

(50 -100 or more)(50 -100 or more)

BUILDING CONSTRUCTION(manufacturing)

OCCUPANCY(use, reuse, maintenance)

DEMOLITION/DISPOSAL

Waste Management

Recycle / Reuse

Products / Materials

MATERIAL ACQUISITION

Raw Material Acquisition

Manufacturing

Products / Assemblies

Focus on relative effects,not absolute numbers!

Life Cycle Assessment is not the same asLife Cycle Costing!

LCA physical units

LCC $Complementarymethods

The LCA toolkitLevel 1 — product focus

1A - for LCA practitioners

SimaPro, GaBi, Umberto

1B - LCA in the background

BEES

Level 2 — assembly focusATHENA® EcoCalculator

funded by GBI for use in GreenGlobes rating system

general use versions coming

Level 3 — whole buildingfocus

ATHENA® Impact Estimator

LCA in the background

Assessment and ratingsystem

Green Globes LEED Minnesota Design Guidelines NAHB Green Home Guidelines

BEES Model (U.S.)

• Focuses on environmental effects and life cycle costs• Provides detailed results for a wide range of impact

indicators• Uses weighting factors to generate environmental and

economic scores• Based on Consensus Standards

LCA-based Level 1 product comparison toolfor use at the specification/procurement stage

BEES 3 Impact Measures

Smog

Global Warming Acidification

Eutrophication Fossil Fuel Depletion

Indoor Air Quality Habitat Alteration

Overall Score

First Cost Future Costs

Carbon Dioxide

Methane

Nitrous Oxide

Ozone Depletion Ecological Toxicity

Human Health

Water Intake Criteria Air Pollutants

Environmental Performance

Score

Economic Performance

Score

LCA-based level 3 whole building tool for use at theconceptual design stage

Shows environmental effects of changes in shape,design or material make-up of a building

Allows designers to optimize operating+embodiedenergy effects over the complete building life cycle

A range of indicators without weighting

Impact Estimator for Buildings

Design 1 Design 2Regional

Electricity GridsTransportation & Product Technologies

Maintenance Schedules Raw Materials Energy Use by type Water Use Emissions to Air Emission to Water Solid Wastes

INVENTORY

Energy Use Global Warming Potential Air Pollution Water Pollution Resource Extraction Effects Solid wastes

SUMMARY MEASURES

BuildingAssemblies

Bill of Materials

Life Cycle InventoriesMaterials & Products

Building ConstructionOperations

Demolition/ Disposal

Energy pre-combustion

effects

. . . informed environmental choices

Picking the Right Tool

Functional equivalence . . .• Want to compare functionally equivalent

products• Choice of one product other choices• Differences in O & M implications• Misleading comparisons more likely for

structure and envelope products

. . . be cautious about product comparisons

BEES

The right data and tool for the task

Generic atconceptual design

Brand specific atprocurement stage

ImpactEstimator

forBuildings

LCA in Assessment, Rating Systemsand Standards

Green Building Standards• GBI/ANSI Standard 01-2007P: Green Building

Assessment Protocol for Commercial Buildings

• ASTM: Standard Specification for the MinimumAttributes of a Building that PromotesSustainability

• NAHB: National Green Building StandardTM

• ASHRAE/USGBC/IESNA Std 189: High-Performance Green Buildings

Could progress over time, from short to long term ideal approach

Option 1pre-rate assemblies

LCA in background

limited demands ondesign teams

more demands on therating organization

focus on materials

simplistic

Option 2decisions based on LCA

design teams may usewhole building LCA tool(s)

could combine embodiedand operations effects

difficult to verify

high educational value

Option 3whole building LCA

high demands on designteams

need benchmarks (onuson rating system orgs.)

combine embodied andoperations effects

supports optimization ofenvelope vs. operations

Options for LCA into rating systems

LCA in Green Globes• LCA education credits at present• Work completed on the assembly ranking approach• Points based on performance relative to benchmarks• Will be included in ANS version of Green Globes

– after public comment and ANSI procedures complete

• Basic tool reviewed by the Building ResearchEstablishment (UK), NIST and others

• Assembly definitions reviewed and refined by the ANSIresources sub-committee

LCA into LEED (US)

• September 2004 kick-off meeting• Working Groups

• goal and scope• technical LCA issues• weighting of impact measures

• Goal and scope WG recommended assemblyranking approach

• Initial focus on MR credits• Accepted by USGBC board• Decision made to start with the EcoCalculator

– research program to detail the approach

Whole House Residential Case Study

Covers embodied effects from resource extractionthrough on-site construction

Results Overview

%

23% difference

Wood-Framed House Componentsby Mass

Concrete 63%

Sheetrock 5%

Insulation 5%

Roofing 5%

Siding 2%

Wood 17%Metal 3%

Although referred to as awood-framed house, concreteis the dominant mass, withother materials playing lesserroles by mass.

If we go to theIf we go to theassembly levelassembly level

Exterior Wall AssembliesRelative GWP

170% difference

New Tool for use inNew Tool for use inRating SystemsRating Systems

Makes such information moreMakes such information moreaccessible to design teamsaccessible to design teams

Impact Estimatorfor buildings

EcoCalculatorfor buildings

LCA-based tool for evaluating and comparingthe environmental effects of assemblies

Currently includes several hundred assemblies Uses 5 environmental impact indicators Regionalized, with more regions under development In rating system, credit better than average performance

for each indicator within an assembly category Generic version, without credit links, is freely available

EcoCalculator for assemblies

Simple to Use

Users only fillin yellow cells

Instant answers

results in spreadsheet form

Wood I-joist and OSB decking system,gypsum board, latex paint

9 tons CO2ecradle to grave

60 year life

EcoCalculatorfor assemblies

3/31/08 42

Key Assumptions• Results on a per unit area basis (e.g., per ft2)

– Estimates based on much larger areas, e.g., 1000 linear feet ofwall

• Owner occupied buildings, 60-year lifespan– Affects maintenance and repair/replacement schedules

• Other specific assumptions:– Window to wall ratio– Concrete strength and fly ash content– Gypsum board type and thickness– Live load for all intermediate floors, columns & beams, roofs– Bay sizes and column heights– External wall thicknesses depending on construction system– Stud size/strength and spacing– Sheathing and decking materials

3/31/08 43

EcoCalculator Versions• Current

– Northern USA averages– Southern USA averages– 8 Canadian regions

• Vancouver, Calgary, Winnipeg, Toronto, Ottawa, Montreal,Québec, Halifax

– 4 US regions• Atlanta, Minneapolis, Orlando, Pittsburgh

• Coming– Los Angeles, New York, Seattle, Phoenix, Denver, +

All with hi-rise and low-rise versions

In Conclusion: LCA tools let you ... Take the environment into account throughout the

project delivery process Focus on true environmental performance measures Look at the entire life cycle of a building Make functionally equivalent material comparisons Recognize and take account of environmental and

economic trade-offs

A FINAL CAUTION:A FINAL CAUTION:BE WARY OF SIMPLISTIC ANSWERSBE WARY OF SIMPLISTIC ANSWERS

TO COMPLEX QUESTIONSTO COMPLEX QUESTIONS

Questions/ Comments?This concludes the:

• American Institute of Architects

Continuing Education Systems Program

www.athenaSMI.ca