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Energy Efficiency and the Law

Learner GuideProduced by Pointsbuild in partnership with the Master Builders

Association of NSW

Supported by the NSW Government as part of the Energy Efficiency Training Program — visit savepower.nsw.gov.au

Energy Efficiency and the Law___________________________________________________________________________________

Copyright and disclaimer The Office of Environment and Heritage and the State of NSW are pleased to allow this material to be used, reproduced and adapted, provided the meaning is unchanged and its source, publisher and authorship are acknowledged. The Office of Environment and Heritage has made all reasonable effort to ensure that the contents of this document are factual and free of error. However, the State of NSW and the Office of Environment and Heritage shall not be liable for any damage which may occur in relation to any person taking action or not on the basis of this document. Office of Environment and Heritage, Department of Premier and Cabinet59 Goulburn Street, Sydney NSW 2000PO Box A290, Sydney South NSW 1232Phone: (02) 9995 5000 (switchboard)Fax: (02) 9995 5999TTY: (02) 9211 4723Email: [email protected]: www.environment.nsw.gov.au

Unit of Competency: CPCCBC4001A 2

Table of contents1 Introduction........................................................................................................................................1

1.1 Energy Efficiency, sustainability and the BCA.............................................................................1

1.2 Background..................................................................................................................................1

1.3 Energy efficiency.........................................................................................................................4

1.4 Energy efficiency and the BCA....................................................................................................5

1.5 Importance of glazing................................................................................................................10

2 Apply building codes and standards.............................................................................................15

2.1 Sustainability: The government background..............................................................................15

2.2 Building codes, standards and regulations................................................................................16

2.3 Conclusion.................................................................................................................................26

3 Classify buildings.............................................................................................................................27

3.1 Introduction................................................................................................................................27

3.2 NCC and classification...............................................................................................................27

3.3 Building determination...............................................................................................................27

3.4 Apply NCC classifications..........................................................................................................32

3.5 NCC Classification issues..........................................................................................................39

3.6 Conclusion.................................................................................................................................39

4 Mandatory performance requirements in low-rise construction.................................................40

4.1 Applying the national construction code....................................................................................40

4.2 Low-rise construction – energy efficiency..................................................................................40

4.3 Six Star energy rating................................................................................................................42

4.4 Low-rise construction: Lighting..................................................................................................67

4.5 Low-rise construction: Natural ventilation..................................................................................68

4.6 Low-rise construction: Sound insulation....................................................................................70

4.7 General installation requirements for walls................................................................................72

4.8 Conclusion.................................................................................................................................76

5 Apply Fire Protection Requirements..............................................................................................77

5.1 National Construction Code (NCC)............................................................................................77

5.2 Passive Fire Control Elements for Low-rise...............................................................................77

5.3 Active fire control elements for low rise.....................................................................................90

5.4 Fire resistance for low-rise buildings.........................................................................................94

5.5 Conclusion.................................................................................................................................97

Appendix A Difficult Classifications......................................................................................................98

Appendix B Classification of Buildings and Structures....................................................................100

Appendix C.............................................................................................................................................102

List of TablesTable 1.1 Climate zones explained.............................................................................................................6Table 2.1 Type of Construction Explained................................................................................................16Table 2.2 Explanation of levels..................................................................................................................19Table 3.1 Building approval process.........................................................................................................28Table 4.1 BCA Application of Energy Efficiency........................................................................................42Table 4.2 Shading Tips..............................................................................................................................44Table 4.3 Thermal Conductivity of Typical Wall, Roof/ceiling, and Floor Materials...................................49Table 4.4 Roof and Ceiling - Minimum Total R-value................................................................................50Table 4.5 Solar Absorptance values..........................................................................................................50Table 4.6 Total R-value for typical roof and ceiling construction...............................................................51Table 4.7 R-values for insulation of roofs and roofs and associated ceilings............................................52Table 4.8 Adjustment of minimum R-value for loss of ceiling insulation...................................................52Table 4.9 Options for each part of an external wall...................................................................................54Table 4.10 Options for each part of an external wall with a surface density of not less than 220kg/m2...55Table 4.11 Total R-value for typical wall construction...............................................................................56Table 4.12 Reflective airspace details.......................................................................................................58Table 4.13 Suspended floor - Minimum Total R-value..............................................................................59Table 4.14 Total R-value for typical suspended floor construction............................................................59Table 4.15 Indicative ranges of whole glazing element performance values............................................61Table 4.16 Worst case whole glazing element performance values.........................................................62Table 4.17 Provision for air movement......................................................................................................63Table 4.18 Heating and Cooling Ductowrk and Fittings - Minimum material R-value...............................65Table 4.19 Application of 3.12.5.6 - Hot Water Supply.............................................................................66Table 4.20 Sound Insulation – State territory...........................................................................................70Table 4.21 Required Rw Airborne and Impact Sound Levels for Separating Walls..................................70Table 4.22 Acceptable forms of construction (NCC Table 3.8.6.2)...........................................................73Table 5.1 Protection of Class 1 buildings..................................................................................................82Table 5.2 Protection of Class 1 buildings..................................................................................................83Table 5.3 Protection of Class 1 buildings - separation of Class 10a buildings on an allotment................84Table 5.4 NCC Bushfire area rules applied...............................................................................................97

List of FiguresFigure 1.1 Household baseline energy use.................................................................................................2Figure 1.2 Australian climate zones............................................................................................................6Figure 1.3 Net daily heat gains through walls and glazing in summer........................................................7Figure 1.4 Daily heat gains and losses through walls and glazing..............................................................8Figure 1.5 Net daily heat flows through walls and glazing in winter............................................................9Figure 1.6 Thermal bridging image............................................................................................................10Figure 1.7 Relative solar gains from eight different orientations during summer......................................12Figure 1.8 Relative solar gains from eight orientations during winter........................................................13Figure 1.9 Shading angle variation between summer and winter.............................................................14Figure 2.1 Structure of the NCC................................................................................................................19Figure 3.1 Identification of Class 1 Building..............................................................................................33Figure 3.2 Typical Class 1 Configurations.................................................................................................33Figure 3.3 Elevation Showing Typical Configuration of Class 1 and Class 2 Buildings............................34Figure 3.4 Domestic Allotment – Classification of Buildings and Structures.............................................38Figure 3.5 Summary of NCC Classes.......................................................................................................39Figure 4.1 Six Star Energy Rating Process Diagram................................................................................43Figure 4.2 Measurement of a projection for wall shading..........................................................................56Figure 4.3 Thermal Mass...........................................................................................................................58Figure 4.4 Insulation of a slab edge..........................................................................................................59Figure 4.5 Attached Class 10A buildings..................................................................................................60Figure 4.6 Method of measuring P and H in glazing calculations.............................................................62Figure 4.7 Breeze Pathways in Domestic Dwelling...................................................................................64Figure 4.8 Method of Determining Areas of Openings for Borrowed Light................................................68Figure 4.9 Method of determining areas of opening for borrowed ventilation...........................................69Figure 4.10 Acceptable location of non-mechanically ventilated sanitary compartment...........................69Figure 4.11 Required airborne and impact sounds insulation - plan view.................................................71Figure 4.12 sound insulation between buildings - staggered stud wall configuration................................72Figure 4.13 Typical installation of plaster sheets for sound insulation......................................................73Figure 5.1 Typical Areas of Potential Fire Spread.....................................................................................78Figure 5.2 Walls at Right Angles to the Boundary.....................................................................................79Figure 5.3 Typical Construction of External Walls.....................................................................................80Figure 5.4 Identifying an Open Carport.....................................................................................................85Figure 5.5 Requirements for non-combustible infill panels to carport.......................................................86Figure 5.6 Allowable encroachment for non-combustible construction.....................................................87Figure 5.7 Separating wall construction....................................................................................................87Figure 5.8 Separating wall construction - underside of non-combustible roof cladding............................88Figure 5.9 Location of combustible roof lights...........................................................................................89Figure 5.10 Location of smoke alarms......................................................................................................90


Figure 5.11 Location of smoke alarms on different storeys.......................................................................91Figure 5.12 Dead airspace and proper mounting of smoke alarms on side walls.....................................92Figure 5.13 Fire place clearance from combustible materials...................................................................94Figure 5.14 Section showing height and position of chimney...................................................................96



1 Introduction

1.1 Energy Efficiency, sustainability and the BCAThe construction of low-rise buildings requires the builder to have knowledge of the building codes and standards relevant to the project. Increasingly, construction of low-rise buildings requires that the project perform to minimum standards designed to improve the energy efficiency and sustainability performance of dwellings and commercial buildings in Australia.

A thorough knowledge of the purpose and contents of the Building Code of Australia (BCA) and the ability to interpret codes and standards to a specific project is required. Builders need to know who is responsible for ensuring that certain design aspects are satisfied at the completion of the project.

1.2 BackgroundSince 2006, the BCA has contained energy efficiency measures for all building classifications. The inclusion of energy efficiency measures in the BCA is part of a comprehensive strategy being undertaken by the Australian, State and Territory Governments to reduce greenhouse gas (GHG) emissions.

Climate change is an issue of major significance for all of us. Most of the world's leading scientists agree that climate change is occurring due in large part to human activity. This presents challenges for the way we live and work and will require action from industry, governments at all levels, the broader community, and individuals.

On 20 November 1997, the Prime Minister released a statement: “Safeguarding the Future: Australia’s Response to Climate Change”. In this statement, a range of measures were announced to address global warming including the need to seek energy savings from the built environment through the introduction of mandatory minimum energy performance standards for all classes of buildings. After a period of consultation with the building industry and key stakeholders, the Australian Government announced in July 2000 that all State and Territory Governments had agreed to introduce mandatory energy efficiency standards into the BCA in order to reduce GHG emissions attributable to the operation of buildings.

The first stage of this initiative was to introduce energy efficiency measures into the BCA Volume Two on 1 January 2003. The next stage was to introduce energy efficiency measures for multi-residential buildings into BCA Volume One on 1 May 2005.

The next stage was to introduce energy efficiency measures into the BCA Volume One for BCA 2006. Also in 2006, the provisions for housing were increased in stringency to 5 star or equivalent.

In 2009 the Council of Australian Governments (COAG) announced that it would ask the ABCB to further increase the stringency of all buildings; for housing to 6 star or equivalent level. DEWHA is the lead Commonwealth agency responsible for managing this project and for future energy efficiency framework projects.



Greenhouse gases – cause and effectGHGs are a natural part of the Earth’s atmosphere. They trap the sun’s warmth and maintain the Earth’s surface temperature at a level necessary to support life. The problem we now face is that human activities, particularly the burning of fossil fuels (such as coal, oil and natural gas) and land clearing, are increasing the concentrations of these gases in the atmosphere, causing global climate change.

There is now little doubt that climate change is occurring. Temperatures, rainfall and known climatic patterns will change. The impacts may be both positive and negative, affecting the distribution of plants and animals, the frequency of storms and floods, and the spread of weeds, pests and diseases which may influence agriculture and our health.

Buildings and energy efficiencyWhile the building sector is not the largest contributor to GHG emissions, it is one of the fastest growing sources. Energy used in buildings accounts for almost 27% of all energy related GHG emissions.

Residential sector energy consumption is estimated to have grown by between 1990 and 2008. Projections to 2020 suggest an increase of 56% over 1990 levels. Improving the energy efficiency of buildings therefore represents one of the most cost-effective ways to reduce GHG emissions in Australia.

The use of renewable or low greenhouse intensity fuels can also reduce the greenhouse emission rate.

Consequently, our industry has an extremely important role in contributing to the abatement of Australia’s GHG emissions and in delivering economic, as well as social and environmental benefits to the community.

Figure 1.1 Household baseline energy use

(Your Home 2008)



Government and industry responsesA multi-pronged approach has been adopted by the Australian Government to improve the energy efficiency of buildings. Firstly, support has been provided by Government and industry for the introduction of minimum energy efficiency Performance Requirements in the BCA which are aimed at setting a community standard. Secondly, industry and consumers are being encouraged to embrace voluntary best-practice initiatives and thirdly minimum energy performance standards have been developed for major items of equipment used in buildings. Finally the Federal and State governments have a range of programs aimed at improving the energy efficiency of the building stock.

DEWHA is assisting industry through the development of practical guide material and associated training courses that help building design professionals and other building practitioners meet and exceed mandatory minimum standards. The ABCB has also commissioned a number of technical reports.

Buildings and sustainabilityBuilding in a sustainable way means living with the natural environment, considering the social, environmental and economic aspects of the decisions we make. It means reducing our footprint by using less energy, water and reducing the high level of consumption of materials. Social sustainability is also important and means developing healthy and safe communities. Sustainability involves a balance that helps the environment and produces economic and social benefits.

The building sector comprises builders, architects, designers and manufacturers. It also includes government regulators, industry bodies, real estate agents and developers all of whom face the challenge of developing sustainability in the built environment. Increasingly, informed customers are demanding more sustainable buildings and communities.

The built environment has in the past and in some cases continues to:

Consume significant amounts of the earth’s resources (especially energy).

Generate polluting toxins and waste.

Create conditions leading to a loss of soils and biodiversity.

Interfere with life support systems (eg. the water cycle, soil systems and air quality).

Exacerbate urban sprawl, traffic pollution, social inequities and alienation

(YourHome 2008)



1.3 Energy efficiency

What is energy?For the purposes of the BCA energy efficiency measures, “energy” is the electricity, gas, oil or other fuels used in buildings for heating, cooling, lighting, hot water supply and the pumping of swimming pool and spa water. It refers to operational energy and does not consider the energy embodied in building materials or invested in the construction and recycling of buildings. The BCA measures for housing do not cover energy used by portable appliances (such as refrigerators, home computers and the like). Some appliances are subject to separate Minimum Energy Performance Standards (MEPS).

Producing electricity or burning natural gas and other fuels releases greenhouse gases into the atmosphere unless the energy source is one of the few considered “clean” sources, such as photovoltaic cells, hydroelectric or wind driven generators. Even these sources will be responsible for emissions at some part of their life cycle. The BCA recognises low-emitting energy sources in its Performance Requirements, Verification Methods and Deemed-to-Satisfy (DTS) Provisions. Since most of the energy consumed in houses comes from greenhouse gas emitting sources, reducing energy use will also reduce emissions and their unwanted impacts.

What is energy efficiency?Energy efficiency is the prudent use of energy resulting from both regulatory measures and voluntary choices, in comparison to the amount of energy that would otherwise have been consumed. Reducing energy consumption by making houses less comfortable and less amenable would result in energy savings but would lead to a lower quality of life, lower personnel output in a commercial environment and possibly poor health. Using less energy for heating, cooling, lighting, supply of hot water, and the pumping of swimming pool and spa water while maintaining expected standards in these areas is the desired outcome. This is the aim of the BCA measures.

Energy efficiency for housing means reducing the load on equipment that directly consumes energy (such as heating and cooling equipment) and the ways that heat flows into and out of the house through its enclosing fabric. This heat flow determines how hard the equipment has to work. Better fabric thermal performance can mean smaller equipment, running for less time.

The stock of houses grows every year and houses remain in use for many decades. Adding houses with poor energy efficiency to the stock means that greenhouse gas emissions will continue to increase and their impact will be felt for a very long time.


FACTS

1. The average house in Australia is responsible for generating 7 million tonnes of greenhouse gases.

2. Conventional energy is generated by the burning of fossil fuels (mainly coal) and is the greatest source of CO2 of any energy source.


1.4 Energy efficiency and the BCASince 2003, the BCA has included Performance Requirements, DTS Provisions and Verification Methods with the objective of reducing greenhouse gas emissions by efficiently using energy and by using renewable energy from low greenhouse intensity sources. Housing measures were introduced first, followed by measures for Class 2 and 3 buildings and Class 4 parts and finally, other building classifications. The Deemed-to-Satisfy Provisions cover:

Insulation to the house fabric (roof, walls and floor),

Measures to control unwanted heat gain or loss through glazing and roof lights,

Measures to reduce air leakage (infiltration) through the envelope and through penetrations of the house fabric such as chimneys and flues,

Measures to facilitate air movement for cooling,

Insulation to hot water supply piping and heating and cooling piping and ductwork,

Measures to reduce greenhouse gas emissions resulting from heaters used for hit water supply systems, electric space heating, artificial lighting and heating and pumping of swimming pools and spas.

The philosophy underpinning these provisions is reasonably straightforward. A number of benefits are obtained by having a house that has better thermal performance. It is likely to stay warmer in cold weather and cooler when the weather is hot. This can reduce the size of any equipment needed for heating and cooling and the occupants are less likely to feel the need to run the equipment. Improving the efficiency of the equipment itself means that it will consume less energy when it is used.

Energy efficiency across warmer and cooler climatesThe DTS Provisions have two approaches. One uses the software of the Nationwide House Energy Rating Scheme (NatHERS) which recognises 67 distinct climate zones. The other approach which is much more prescriptive and less flexible contains building solutions based on eight climate zones (Refer to Figure 1.2 for the extent of these climate zones). With both approaches there are different elemental DTS Provisions for each climate zone.

Note that the Figure 1.2 climate zone map is based on both climate data and local government boundaries, so it may change from time to time in response to changes in those local government boundaries. The more numerous NatHERS climate zones are based on both climate data and postal districts.


TIP

Energy Efficiency is the best way to reduce energy bills without compromising comfort levels in the home.


Figure 1.2 Australian climate zones

Table 1.1 Climate zones explained

Climate Zones Description

1 & 2Locations with hot or warm and humid summers and warm or mild winters where a desire for cooling is likely to predominate for most of the year

3 & 4Hot dry summers and warm or cool winters so that both cooling and heating may be desirable. In climate zone 4, a need for heating is likely to be felt for more of the year than a need for cooling

5 A warm temperate climate with limited need for cooling or heating although, in balance, the need for heating is likely to be greater

6 & 7 Cool temperate climates respectively, with the winter cold enough to require significant heating

8 An alpine climate where heating is the predominant need

Energy efficiency in warmer climatesFor our hotter or warmer climates, climate zones 1, 2 and 3, the intent is to limit the need for cooling services (which use electricity which has higher greenhouse gas intensity than natural gas). In these climates, heating is needed less frequently if at all.



The BCA elemental DTS Provisions for these locations, such as thermal insulation, favourable orientation and shading of glazing, sealing against air infiltration etc., are primarily aimed at reducing unwanted heat gain. Unwanted heat gain may increase discomfort levels in the building to a point where the occupants would want to turn on an air-conditioning system. Untreated glazing can be the main avenue for unwanted heat gain in summer or throughout the year in the hottest climates. This is shown diagrammatically by the size of the arrows in Figure 1.3 which illustrates typical heat flows through the fabric and glazing of a bungalow over twenty four hours in January. Section 1.4 (pg10) of this chapter discusses in detail the impact of glazing.

Figure 1.3 Net daily heat gains through walls and glazing in summer (January day in Brisbane, balcony facing north)

(YourHome 2008)

Note: The relative net gains through glazing and insulated walls are indicated by the length of the arrows. No transfer through the ceiling or floor is shown because there are other Sole-Occupancy Units above and below. Note that the greatest net gains are through the east facing glazing panel 2 although it is not the largest area of glazing.

Energy efficiency in colder climatesThe coldest climates are found in climate zones 7 and 8. Climate zone 8 is the only strictly alpine climate and even it is much milder than alpine locations in other parts of the world. For houses in these cold climates, the intent is primarily to reduce the need for heating services although there may still be some use of cooling services as well in commercial buildings with a high internal load from computers and process plants. Provisions addressing the thermal insulation of the envelope, the size and type of glazing



used, the level of air infiltration etc. are mainly aimed at reducing unwanted heat loss through the envelope, while making use of wintertime solar gains

External glazing can be the main avenue for heat loss due to conduction through the glass and frame unless they have enhanced insulating properties or are oriented to make good use of winter sunshine. Refer to Figure 1.4 (showing Hobart) and to Chapter 7 which describes the elemental DTS Provisions that regulate the performance of external glazing to reduce this heat.

Figure 1.4 Daily heat gains and losses through walls and glazing (average July day in Hobart, balcony facing north)

(YourHome 2008)

Note: The relative heat flows are indicated by the length of the arrows. Lighter arrows indicate solar heat gains and darker show conducted heat losses. (The lower arrow is always the larger). Heat losses through all walls and glazing exceed the gains except for the north facing glazing panels 3 and 4

Energy efficiency in temperate climatesMany Australians live in areas that have four seasons a year. These areas are found in climate zones 4 to 6, with even climate zone 2 in this category to some degree. These climate zones have warm to hot summers and cool to cold winters. Spring and autumn temperature ranges are generally mild. Building conditioning systems will, at different times, have a need for both heating and cooling to cater for the extremes of the seasons and, therefore, the BCA measures address both heating and cooling.



Thermal treatment of the building envelope is beneficial in both hotter and colder weather. In summer, limiting heat gain can reduce the desire of occupants to run any cooling services installed. In winter, the building fabric can reduce the heat loss (via conductance) to the outside and can also promote solar heat gains (through good orientation and treatment of glazing) to offset the conductive heat losses

Refer to Figure 1.5 as an example showing the net result of inward and outward heat flows over the 24 hours of a typical winter day through the fabric and glazing of a Class 2 sole-occupancy unit in Sydney in July.

Figure 1.5 Net daily heat flows through walls and glazing in winter (average July day in Sydney, balcony facing north)

(Your Home 2008)

Note: Note that lighter arrows indicate solar heat gains and darker show conducted heat losses. All surfaces produce net heat losses except the north facing glazing panels 3 and 4. The net gain for glazing panel 3 is tiny. The largest net loss is through the east facing glazing panel 2


DESIGN ALERT

It is likely that some cooling or heating services will be installed in buildings. The BCA is trying to reduce the use or size of heating and cooling systems, not trying to eradicate them.


1.5 Importance of glazing

Importance of glazing in housesAll elements of a house’s fabric present opportunities for energy savings. It should be noted that the higher the floor above the natural ground, possibly to capture a breeze, the greater the wind pressure, and as a result, the greater the potential for infiltration or leakage through the building envelope and around glazing.

The BCA measures emphasize the importance of maintaining the thermal performance of the fabric, and this is highlighted in the Verification Method V2.6.2. Heating and cooling equipment may be replaced many times over a house’s life but fundamental fabric measures such as wall insulation, window sizes, shading, orientation and air tightness need to remain for the life of the house.

For a unit or space with limited external fabric, glazing can become the greatest source of heat transfer and of infiltration or air leakage, making it the critical element in achieving energy efficiency.

Figure 1.6 Thermal bridging image

Importance of glazing generallySome glazing systems commonly used in Australian houses can have thermal insulation qualities that are poor compared to other parts of the house fabric. We heavily insulate some elements of the bounding envelope of our houses (such as walls, floors and roofs) against heat transfer yet significant heat transfer can occur through the windows unless drapes and shading devices are managed appropriately.



In summer, sunlight radiates through the glass, bringing unwanted heat into the interior. However, in winter, solar heat gains through the glass can contribute usefully to the energy efficiency of a house where heating is desired.

The provisions contain requirements for the thermal performance of glazing (including frames) depending on the glazing area, its orientation and the extent of any shading. This attempts to limit unwanted heat gain into the house in hot weather without unduly restricting the potential for solar heat gains in winter

Glazing – the main opportunity to improve energy efficiencyPoorly designed glazing can become the main thoroughfare for unwanted heat gain or heat loss. However, with the correct design, windows and glazed doors may provide an opportunity to achieve greater energy efficiencies within the house by:

maximising solar heat gains in cooler seasons lessening the need for heating;

minimising unwanted heat gains in hotter seasons lessening the need for cooling;

opening the house to air movement for cooling during the night in hot seasons; and

providing natural light which can reduce the use of heat-producing artificial lighting in the house during daylight hours

If used carelessly the glazed elements risk becoming a major weakness in the insulated building envelope. The provisions in BCA Volume Two under Part 3.12.2 are intended to keep unwanted energy flows through the glazing within limits that are considered reasonable for each climate zone. In some house types in some locations, greater energy efficiency can be achieved by also making use of desirable solar gains in the colder periods.


DESIGN ALERT

For climate zones 2 to 7, external walls of a house may have a Total R-Value of around R2.8 while basic clear single glazing in an aluminium frame with a U-Value of 7.9 equates to an R-value of 0.13 (the reciprocal of the U-Value, 1/7.9).

Therefore the external wall insulates over 20 times better than the basic, clear, single glazing.

DESIGN ALERT

One of the main considerations in the design of mechanical equipment for a house is the heating or cooling load resulting from the glazing. Correctly designed glazing may reduce the size and capacity of the heating and cooling equipment needed in a house.


Building orientation affects glazing energy efficiencyA comparison between Figure 1.7 and Figure 1.8 illustrates how windows can receive beneficial winter sun but not unwanted summer sun.

Figure 1.7 shows the relative size of the total solar gains from eight different orientation sectors through unshaded glazing in Brisbane during the three months from December to February. The centrelines of the main sectors (North, South, East and West) are marked by solid lines. The sectors in-between align to North East, South East, South West and North West. The length of each “pie slice” shows the relative amount of solar gain from that direction.

Figure 1.7 Relative solar gains from eight different orientations during summer(December to February in Brisbane)

It is obvious that glazing facing the North or South sectors receives the least solar energy and much less than glazing facing the East and West sectors. (In fact, North or South facing glazing receives just half of the summertime gains of East and West facing glazing).

Gains from any of the intermediate sectors are about equal to each other and closer in size to the East and West gains than they are to the North and South. Although the diagram illustrates the situation in Brisbane, the pattern is broadly similar in most other Australian locations. It suggests that the North and South orientation sectors are particularly favourable for summer conditions.

Figure 1.8 is the wintertime version of Figure 4.2, showing the relative size of the total solar gains from the same eight orientation sectors in Brisbane during the three months from June to August. It is drawn at the same scale as the summertime diagram so that the size of “pie slices” on both diagrams can be compared directly.



Figure 1.8 Relative solar gains from eight orientations during winter(June to August in Brisbane)

What might be unexpected is that the North sector is the largest source of solar gain during winter and the East and West sectors provide energy gains that are less than half of those available from the North. This is a complete reversal of the summertime situation.

Gains from the intermediate North East and North West sectors again fall somewhere between the two. The remaining sectors (South East, South and South West) provide negligible gains during the months when they are most desirable.

Combining the summer and winter outcomes shows that the East and West sectors provide the highest level of unwanted summertime energy gains but less than half of this during winter when solar gains are likely to be beneficial. The South sector provides the lowest summertime energy gains but virtually no useful energy gains in winter.

By contrast, the North sector has the same advantage during summer as the South sector but is the best source of desirable solar gains during the winter months. This combination identifies the North orientation sector as uniquely favourable for avoiding heat gains when they are not wanted and being able to make use of them when they will be most beneficial.

The North East and North West sectors provide comparatively high levels of solar gains all year round, whether or not they are welcome. The South East and South West sectors have the disadvantage of high summertime energy gains with minimal compensating benefit in winter.

Orientation is not directly important for conductance. Whether a window faces North, South, East or West, the same amount of heat loss is calculated to occur because the loss depends on the air temperature inside the house compared to the air temperature outside, which is assumed to be similar in



all directions. Good orientation, however, can compensate for heat lost through conduction by providing offsetting solar gains.

Sun angles affect energy efficiency of glazingThe winter sun appears lower on the horizon at any time of day than the summer sun at the same time. Between the lowest winter position and the highest summer position there is a difference of about 47°. For an unshaded window, the angle of the sun’s rays onto the glass will affect the amount of solar heat gain transmitted through the glass. The sharper the angle (closer to 90° from the horizontal), the greater the reflectance from the surface of the glass, which results in less solar heat gain. This is most effective in summer as the sun is higher in the sky and thus the angle is sharper, whilst the winter sun is lower in the sky and the angle is more direct. The effect of this and the differing hours of sunshine between the seasons is reflected in the previous diagrams Figure 1.7 and Figure 1.8, which illustrate results for unshaded glazing.

Another important benefit of the changing sun angles is that it is possible to provide shading devices that protect glazing from unwanted summer sun while allowing the lower winter sun to shine directly into the windows providing heat gains when they may be welcome (refer to Figure 1.9)

Figure 1.9 Shading angle variation between summer and winter

(YourHome 2008)



2 Apply building codes and standards

This chapter looks at the application of building codes to the construction of low-rise developments, with a focus on sustainability measures. In order to understand sustainability and its importance to the National Construction Code (NCC), this chapter begins with ecologically sustainable development and the approach of governments throughout Australia. The application of sustainability is addressed by looking at the goals of the NCC and how the ‘rules’ are actually applied, including a look at the flexibility of the rules to ensure the goals are met.

2.1 Sustainability: The government background

Performance and constructionThe construction of low-rise buildings requires the builder to have knowledge of the building codes and standards relevant to the project. Increasingly, construction of low-rise buildings requires that the project perform to minimum standards designed to improve the energy efficiency and sustainability performance of dwellings and commercial buildings in Australia.

A thorough knowledge of the purpose and contents of the National Construction Code (NCC) (formerly the Building Code of Australia (BCA)) and the ability to interpret codes and standards to a specific project is required. Builders need to know who is responsible for ensuring that certain design aspects are satisfied at the completion of the project.

Ecologically sustainable developmentEnergy efficiency and sustainability has been identified as an important issue by the Australian Building Codes Board (ABCB). The ABCB is established by agreement between the Australian Government and each State and Territory Government. It is a co-operative arrangement between the signatories, Local Government and the building industry.

Reform of regulations and industry across Australia is generally coordinated by the Council of Australian Governments (COAG)1. The National Strategy for Ecologically Sustainable Development (NSESD) was endorsed by Heads of Government in 1992. The NSESD provides broad strategic directions and framework for governments to direct policy and decision-making.

Australia's National Strategy for Ecologically Sustainable Development (1992) defines ecologically sustainable development as: 'using, conserving and enhancing the community's resources so that ecological processes, on which life depends, are maintained, and the total quality of life, now and in the future, can be increased'.

Since 1997, the NCC has had a performance-based approach to regulation and this has included sustainability factors. In 2004, the NCC was published annually as a two volume edition. In 2011, the National Construction Codes Series was established. In order to gain national consistency, the

1 The Council of Australian Governments (COAG) is the peak Inter-Governmental forum in Australia, comprising the Prime Minister, State Premiers, Territory Chief Ministers and the President of the Australian Local Government Association (ALGA)



performance-based criteria allow for the construction of buildings that best suit their local climatic conditions. There are 8 broad climate zones across Australia.

Low-rise buildingsLow rise constructions will include:

class 1 or class 10 buildings - BCA Volume 2 and relevant state code variations

class 2 to 9 buildings – BCA Volume 1

with a floor area not exceeding 2000 m2

not including Type A or Type B construction

Type A and Type B constructionThe type of construction (ie. A, B or C) generally refers to:

the class of the building

the number of storeys in the building

Hence, the requirements for fire resistance rating and fire safety of the building.

Type A construction is the most fire-resistant and Type C the least fire-resistant of the Types of construction.

Table 2.2 Type of Construction Explained

Rise in storeys Class of Building2, 3, 9

Class of building5, 6, 7, 8

4 or more A A

3 A B

2 B C

1 C C

2.2 Building codes, standards and regulationsThe legislation that governs all technical building matters varies in each state but under this Act the National Construction Code is called up as the 'Building Rules' applicable in each state and territory.

The Regulations in each state (Appendix 3) also introduces rules that must be followed during the development process. Levels of fines and penalties exist for failing to comply with these regulations.

The Building Codes are a systematic set of laws or rules while Standards are a required or specified level of excellence.



There are a range of documents that control building planning and development across Australia as follows

National Construction Code (NCC)The National Construction Code (NCC) is a national performance-based building code that presents the minimum technical building regulations for design, construction and performance in Australia. It is accepted through State and Territory legislation as the primary technical standard for their building regulation system.

The NCC is produced on a twelve monthly cycle and each new edition contains changes from previous editions and becomes law on May 1 or when adopted by the States or Territories.

Note - In May 2011, the National Construction Code (NCC) was rolled out, replacing the Building Code of Australia:

Goals of the NCCThe goals of the BCA are to deliver minimum acceptable standards of:

structural safety

safety from fire

sustainability

health and amenity

Maintaining the NCC



The Australian Building Codes Board (ABCB) is responsible for the continuing development of the NCC. It was established in 1994 by agreement between the Australian Government, each State and Territory Government, local government, signatories and the building industry.

The ABCB’s mission is to achieve national consistency in community expectations of safety, health and amenity in the design, construction and use of buildings through nationally consistent, efficient and cost effective technical building requirements and regulatory systems.

The Board comprises —

the Australian, State and Territory Governments' principal officer responsible for building regulatory matters;

a representative of the Australian Local Government Association (ALGA); and

industry representatives.

The Building Codes Committee (BCC) is the peak technical advisory body to the ABCB, with responsibility for technical matters associated with the BCA. The BCC comprises—

the Executive Director of the ABCB;

one nominee each of the Australian, State and Territory Governments' and ALGA members of the ABCB; and

industry members appointed by the ABCB.

Notes are prepared by the ABCB to assist NCC users. The ABCB annually amends the NCC. In conjunction with the amendment the ABCB prepares notes that provide a description of changes from the previous edition of the NCC. These notes can be found on the ABCB website.

Structure of the NCCThe NCC is published in three volumes.

Volume One: relates primarily to Class 2 to 9 buildings (commercial sector), plus some issues relating to Class 10 buildings

Volume Two: relates to Class 1 and Class 10 buildings (domestic sector), plus some Class 10 structures

Volume Three: relates to plumbing guidelines

The structure of the NCC is shown in Figure 2.10.



Figure 2.10 Structure of the NCC

The structure of the NCC is in four levels but only one level is mandatory.

Table 2.3 Explanation of levels

Guidance Levels

Objectives - aim to reflect community expectations

Functional Statements - describe how a building achieves the Objectives

The Objectives and Functional Statements provide guidance when interpreting the NCC and should not be used to assess compliance with the NCC.

Compliance Levels

Performance Requirements MANDATORY Building Solutions

- Deemed-to-Satisfy (DTS)- Alternative Solutions- Combination of both

Energy efficiency and sustainability have both been noted in the Objectives and Functional Statements.

The NCC as a written documentThe NCC refers to Applications and Limitations. These terms are merely used to show when an Objective, Functional Statement and Performance Requirement applies or does not apply.

The term “to the degree necessary” also appears frequently. This phrase is used to show that provisions can differ according to various elements which appropriate authorities may take into consideration when assessing building applications.



For instance, it could be argued that if the fire compartment of a building is quite small then perhaps it is not necessary to install a fire-hose reel system. This is borne out by the Deemed-to-Satisfy Provision which states that such a system is only compulsory in a building having a floor area greater than 500m2.

Relevant performance requirementsNo NCC provision can be considered in isolation. Any departure from the Deemed-to-Satisfy (DTS) Provisions for an Alternative Solution needs to be assessed against the relevant Performance Requirements within the relevant NCC Section or Part.

Additionally, the proposed Alternative Solution may also impact on other Performance Requirements in other NCC Sections or Parts. Thus, these additional Performance Requirements need to be considered in relation to the subject Alternative Solution

Regulation within the building industryThe content of the different building regulation systems across each Australian State and Territory is reasonably similar.

The need for building work to be regulated is to manage the following:

protection of people

protection of property

promotion of sustainable development

main sources of risk to life

health and amenity issues

acceptable levels of risk

assessment of rigorous cost/benefit analyses

establishment of minimum standards.



Building regulation systems usually include two types of regulation:

Administrative Regulations

Examples of Administrative Regulations include:

powers and responsibilities of parties

assessment procedures

referrals, objections and appeals

inspection and certification processes

offences and penalties

adoption of the NCC.

Technical Regulations

Examples of Technical Regulations include:

design and construction requirements for buildings and structures

building requirements such as –

Protection of adjoining property during construction

Hoardings to protect the public

Signage to warn the public of hazardous materials.

State and territory legislation and building codes

There are legislative acts and regulatory requirements for the building and construction industry that need to be applied in addition to the building regulations, codes and standards listed above.

Key relevant legislation for the building and construction industry is often based on state and territory legislation. Some legal areas that affect building work you may perform include:

Area AreaPlanning and development Gas installationsBuilding work contractors Historic buildingsFlammable liquid storage HousingHealth Care buildings Lift installationsFood Service buildings Movable dwellingsAccommodation Occupational Health & Safety

Asbestos removal Sanitary plumbing, water supply & sewerage

Crown land septic tank and grey water installationElectrical installations subdivision of property

Fences waste management and environmental protection

Fire prevention in existing buildings

State and territory variations and additionsEach State’s and Territory’s legislation adopts the NCC subject to the variation or deletion of some of its provisions, or the addition of extra provisions.

In the Volume Two, Housing Provisions, these are divided into two types:



(a) A variation to the Housing Provisions — these are identified following the clause that is being varied.

(b) Additional requirements — these are contained in NCC Volume Two, Appendix A

Performance requirements for low-rise projectsThe Performance Requirements listed in the NCC are mandatory. All new buildings must be designed to comply with all appropriate Performance Requirements. The compliance with NCC Performance Requirements is required by governments to achieve community expectation.

The means of compliance with a Performance requirement is termed a 'Building Solution' of which there are two parts:-

Deemed to Satisfy provisions and

Alternative Solutions

A builder or designer may choose to design the building based upon compliance with the performance requirement through the use of the DTS provisions, or an alternative solution or both.

A performance based code has many benefits.

Improve cost efficiency

Improve constructability

Incorporate innovation

A building designer may choose to comply with the performance requirement by using either the DTS provisions or Alternative Solution or by a combination of both.

Performance requirements may need to include:

those contained within other legislation applicable to a specific project

performance requirements of the NCC determined to be relevant to a specific project

performance-based contractual requirements that must be fulfilled by any party

Two examples of Performance Requirements to satisfy NCC Volume Two are outlined below:

Performance requirement – building sealing

P2.6.1 states that a building “must have, to the degree necessary a level of thermal performance to facilitate the efficient use of energy for artificial heating and cooling”. This can be satisfied with the sealing of a window if the air filtration of the closed window complies with AS 2047.

Performance requirement - Services

Insulating sanitary hot water service piping can satisfy the performance requirement of P2.6.2. The NCC is focussed at reducing greenhouse gas emissions. Increasing energy efficiency by insulating hot water pipes increases the operational savings in a home as well as reducing greenhouse gas emissions.



Deemed-to-satisfy (DTS) provisionsThe NCC provides a range of building solutions that are optional and are called Deemed-to-Satisfy as they are deemed to satisfy the mandatory performance provisions.

Performance based regulations provide flexibility in the building industry by allowing alternate acceptable options to standard practice. DTS provisions allow for building standards to be practiced that were legislated prior to the NCC.

DTS provisions make up the bulk of the NCC and if used are accepted as conclusive proof of compliance.

A Building Solution which complies with the Deemed-to-Satisfy Provisions is deemed to comply with the Performance Requirements.

For example – Blockwork walls (energy efficiency of the building envelope)

Certain blockwork wall products and systems are deemed to satisfy the NCC. In particular, products can show that they satisfy NCC Table 3.12.1, 3(b) options for external walls with a surface density not less than 220kg/m2. Many manufacturers have released specifications showing that use of their products will satisfy the NCC.

Alternative solutions to design or construction problemsAlternative Solutions are how to comply with the NCC without using DTS provisions and provide a means of meeting the performance requirement by a method that is at variance to the deemed to satisfy provisions. Their use may delay the design and approval process as proof of compliance with the Performance Requirement will be required.

The use of an Assessment Method as prescribed in the NCC will be satisfactory.

Alternative Solutions may be used to:

incorporate innovation

address anything different to Deemed–to–Satisfy.

An Alternative Solution must be assessed and verified by an appropriate certifying authority. If the certifying authority is not satisfied that the applicant has demonstrated compliance then the proposal for the Alternative Solution is not approved.

For example: - building projects on heritage buildings might involve significant difficulties with existing features and building envelopes.

For Alternative Solutions, it might be necessary to consider including the installation of new sustainability measures such as energy efficient HVAC, hot water systems, water tanks and other energy efficient systems that may offset some of the less energy-compliant fabric and features of the heritage building.

There is a degree of flexibility within the NCC. However, when using an Alternative Solution, it is important to ensure that it complies with all parts of the NCC.



Assessment methods for alternative solutionsA building solution must comply with the Performance Requirements. The following Assessment Methods, or any combination of them, may be used to determine compliance

Forms of Evidence

Forms of evidence include:

Reports from a registered testing authority

Certificate from a professional engineer

A current Certificate of Conformity.

Refer to the NCC Volume 2, Part 1.2.2.

Verification Methods

The verification methods are:

Listed in the NCC,

Include others that are acceptable to an appropriate authority

the third form of a Verification Method might include:

o calculations using analytical methods or mathematical models;

o tests using a technical procedure, either on site or in a laboratory, to directly measure the extent

o performance requirements are achieved; or any other method, including an inspection (and inspection report).

Comparison with Deemed-to-Satisfy

As listed in the NCC

Expert Judgment

Assessment Methods are the means by which a building proponent proves that an application for a building permit meets all requirements.

NCC Assessment Methods include a method which accords with the requirements of NCC Volume 1 - A2.2;

All Verification Methods must:

be acceptable to the Appropriate Authorities eg. the local council etc

use Assessment Methods to determine whether an application has met all requirements. For example, when processing a building consent, authorities might check to see that a qualified



expert has offered an opinion, and, most importantly, found the application to comply with the NCC. This is just one of many options available

Performance based solutionsPerformance-based solutions for low rise are identified and documented in accordance with NCC requirements and organisational quality procedures and processes

Performance based solutions that allow for facility and technology improvements to be made within existing budgets are usually designed to reduce operating costs while providing the additional value of new, energy efficient equipment. Through innovative performance based solutions, clients can be advised that investments will be paid off in the future through considerable energy savings

Private Certifiers are able to assess Performance Based design solutions in order to achieve cost effective solutions to a building project without compromising the performance objectives of the Building Code.

For example, From a heritage viewpoint, possibly the most beneficial way of achieving compliance for alterations and additions to existing heritage buildings is to develop an Alternative Solution. Using this approach, the retention of perceived thermally inefficient building fabric for heritage reasons may be considered if it can be compensated by innovative design strategies.

Compliance with performance requirements or DTS provisionAssessment methods referenced in the NCC to determine whether a building solution complies with performance requirements or DTS provision of the NCC are analysed and applied

evidence of suitability as described in the NCC

expert judgement as defined in the NCC

verification method as defined in the NCC

In order to comply with the provisions of the NCC for Classes 2-9 the following method must be used to determine the Performance Requirement or Performance Requirements relevant to the Alternative Solution:

(a) Identify the relevant Deemed-to-Satisfy Provision of each Section or Part that is to be the subject of the Alternative Solution.

(b) Identify the Performance Requirements from the same Sections or Parts that are relevant to the identified Deemed-to-Satisfy Provisions.

(c) Identify Performance Requirements from other Sections and Parts that are relevant to any aspects of the Alternative Solution proposed or that are affected by the application of the Deemed-to-Satisfy Provisions, that are the subject of the Alternative Solution



Relevant Australian standards

Standards Australia define a Standard as:

A Standard is a published document which sets out specifications and procedures designed to ensure that a material, product, method or service is fit for its purpose and consistently performs in the way it was intended.

There are nearly 200 Australian Standards that are ‘called up’ by the NCC. These Standards must be observed whenever they are relevant to a building, a construction activity, a material or other component being used on a particular project.

Builders are expected to be aware of and comply with the relevant Australian Standards. Standards provide advice on building and construction work and plant and equipment safety. There are over 200 Australian Standards referenced in the NCC – see Volume 1 Section A1.3 or Volume 2 Part 1.4.

For Australian Standards commonly used in commercial buildings see Appendix B

2.3 ConclusionIn this chapter, we have covered off the background to sustainability from a government perspective, and its application to building in Australia. The National Construction Code is the set of rules that allow the sustainability (and other) goals of the Australian Building Codes Board to be applied to construction projects.

You can now appreciate that sustainability need not be burdensome and in fact can be applied with a certain amount of flexibility under the NCC. This knowledge will now enable you to better consult with potential clients and architects ensuring that the dwellings you build have a better ongoing performance for future occupants.



3 Classify buildings3.1 IntroductionTraditionally, the construction of buildings in Australia, including the safety, health and amenity of occupants, is a matter for the States and Territories to supervise and legislate over. This is because the constitution does not refer to these issues and therefore it is not something that the Australian government has constitutional power over. However, the lack of national guidelines was subject of State and Territory interest since post-World War WII. In the 1990’s the Australian Building Codes Board (ABCB) was established. Each State and Territory has implemented legislation that refers back to the National Construction Code.

Due to the range of building types, a classification system has been implemented ranging from Class 1 to Class 10 (see below). The classification system enables the regulations to broadly cover the construction of buildings of different types with rules relevant to each Class. Local Councils develop Local Environment Plans (LEPs) which specify what types of buildings can be built in particular areas. For example, a factory cannot be built in an area which has been zoned ‘residential’.

This chapter will provide you with an understanding of the classification system, including the reasons for it. Further, this chapter is important because the classification of a building will affect the energy efficiency measures that may apply. Understanding building classification will mean that you can better apply the National Construction Code (NCC.)

3.2 NCC and classificationA building, part of a building or structure is classified by the purpose for which it is designed, constructed or adapted to be used. Buildings and structures must be classified as set out by the NCC. Refer to the NCC Volume 1 Part A3 Classification of Buildings and Structures or Volume 2 Part 1.3 Classification.

If there is any doubt as to the classification of a building under the NCC a building surveyor must classify the building as belonging to the class it most closely resembles. Classification is determined by particular factors such as the activities undertaken within the building, the nature of the occupants (related/non-related), and the number of occupants.

ClassificationLow rise falls within the NCC classifications:

Class 1 and class 10 buildings

Class 2 to Class 9 buildings with a gross floor area not exceeding 2000m2 not including Type A or Type B construction.

For further explanation about the classifications refer to Appendix B.

3.3 Building determination

State and Territory Acts and RegulationsThe NCC is given legal effect by building regulatory legislation in each State and Territory. This legislation consists of an Act of Parliament and subordinate legislation that empowers the regulation of



certain aspects of buildings and structures, and contains the administrative provisions necessary to give effect to the legislation.

Any provision of the NCC may be overridden by, or subject to, State or Territory legislation. The NCC must therefore be read in conjunction with that legislation. Any queries on such matters should be referred to the State or Territory authority responsible for building regulatory matters.

Planning approval is granted when an application meets the building rules as set out in the NCC and/or state and territory codes. The terminology for this approval process varies across each state/territory and the titles used are summarised in Table 3.4 below.

Table 3.4 Building approval processState/ Territory

Building Regulatory Legislation

No Approval required or Provisional approvals

Complying development

Overseeing Govt Dept

ACT Building Act 2004 Development Approval

Building Approval ACT Planning and Land Authority

NSW Environment Planning & Assessment Act 1979 & Regulations 2000

Complying Development Certificate (CDC)

Approved development application and a Construction Certificate

NSW Dept of Planning

NT Building Act, Building 2010 & Regulations 2010

Permit to Build Building PermitOccupancy Permit (on completion)

NT Lands Group

QLD Building Act 1975 Building Rules approval

Building Services Authority

SA Development Act 1993 & Regulations 2008

Provisional Development Plan ConsentProvisional Building Rules Consent

Development Approval

Dept of Planning and Local Government

TAS Building Act 2000 Planning Permit Building Permit Dept of JusticeConsumer Affairs and Fair Trading

VIC Building Act 1993 & Regulations 2006

Building Permit Certificate of Consent

Building Commission Victoria

WA Local Government (Miscellaneous Provisions) Act 1960, Building Regulations 1989

Building Permit Dept of Commerce Building Commission Western Australia



The authority that issues the building development approval is usually the local shire or council, except for some minor state and territory circumstances as set out in their Acts. A development will be taken to be an approved development when all relevant consents have been granted and the development authority (usually the Council) has issued a notice of ‘development approval’ or similar (see table above).

An applicant may be able to choose to engage a private certifier (instead of the Council) to assess the application against the provisions of the Building Rules. Where it is proposed to engage a private certifier and the applicant is not the owner of the land, the person who wishes to engage the private certifier must obtain written consent from the landowner.

If a private certifier is engaged the private certifier must notify the shire or council of their engagement. Only the relevant authority (shire or council) can issue the final development approval.

The requirements for an Owner/builder vary greatly across states and territories with some states requiring completion of a training program before commencing. They will also need to satisfy the shire or council that the proposed development will comply with any planning policies and principles applicable to the site, as set out in the development plan for the shire or council area and with any existing conditions of consent.

The shire, council or private certifier may require certification that the proposed construction will be structurally adequate and/or that it will provide for an acceptable standard of health and safety.

In addition, buildings on a State/Territory Heritage Register or a local heritage register may be subject to additional requirements relating to the degree of change, which is deemed appropriate. Any addition should respect the scale and character of the original building as well as the original fabric and should involve minimal physical intervention. Additions to heritage listed buildings may include alterations to, or restoration of, the existing building as well as upgrading of services and finishes. (Refer to the relevant planning authority for details of heritage requirements).

Building work requiring approvalUnder the various ‘Acts’, “building work” means work or activity in the nature of:

(a) the construction, demolition or removal of a building; or

(b) the making of any excavation or filling for, or incidental to, the construction, demolition or removal of a building; or

(c) any other prescribed activity.

Building a house, making structural alterations or adding to an existing house is building work and will require a development approval. All other building work, except that are listed in various exempted Schedules in each state/territory, requires development approval, before it is commenced.

Approvals required for building work generally associated with residential development are set out in Acts and various state/territory codes and publications.



Applying for development approval/building permitPrior to undertaking any building work, development approval must be obtained, for which an application must be lodged with the shire or council. A fee must be paid at the time the application is lodged and all drawings, specifications and calculations related to the application must be submitted. In addition, the applicant must advise if the documentation has been prepared in accordance with the NCC or approved housing codes for each state/territory.

Most Councils and private certifiers require at least two copies of supporting documents, although more can be required under the legislation.

To apply for consent to construct a Class 1a or Class 10a building, the following documents are required:

(a) a site plan drawn to a scale of not less than 1:500 showing site dimensions, allotment boundaries, sewer or other easements and all existing features on the land. Any building work proposed over an easement shall have written consent from the easement holder. The site plan shall clearly indicate the location of the house and any other buildings (existing or proposed). Site levels, water table levels and floor levels shall be clearly indicated, together with details of proposed drainage and services for shire/council assessment of drainage;

(b) floor plans drawn to a scale of not less than 1:100;

(c) elevations and sections drawn to a scale of not less than 1:100;

(d) footing plan and roof framing plan drawn to a scale of not less than 1:100 and any structural details which the shire/council may require drawn to a scale of not less than 1:20;

(e) any other details which the shire/council may consider necessary to clarify the application drawn to a scale of not less than 1:20;

(f) a specification describing materials and workmanship and any other information not indicated on the drawings that shire/council may require;

(g) any necessary structural calculations and reports to supplement design criteria;

(h) details in writing of any foundation investigations that have been carried out; and

(i) statement of design wind speed.

Where any demolition is proposed, the shire/council or private certifier will require a site plan showing the extent of the demolition, other buildings on the site and any other relevant information, a description of the building, and if only part of the building is to be demolished, any necessary drawings and calculations to show that the remaining building will comply with the Building Rules.


NOTE

Since 2005 in NSW, development applications must be accompanied by a BASIX certificate. The BASIX certificate contains a list of the commitments which the applicant has made to promote the sustainability of the proposed development.

It is a condition of the development consent granted that the BASIX commitments be complied with.


Where any excavation or fill is proposed, the shire/council or private certifier will require a site plan showing existing and proposed levels, distances from allotment boundaries and other buildings on the site and any neighbouring sites which are likely to be affected, drainage and services proposed and any other relevant information. Depending on local shire/council requirements, where excavation or filling is proposed, notification may need to be given to owners of any land nearby which may be affected by the proposed work.

A shire/ council or private certifier may ask for additional information, and the shire/ council has power to refuse the application if the applicant does not provide this. An application may be amended before approval is granted with the consent of the shire/council.

Professional CertificatesThe Acts and the NCC allow for certificates from professional consultants to be used as evidence of compliance with particular requirements or standards.

The Act also contains provisions for private certifiers to carry out some of the duties normally undertaken by the shire/council in relation to assessment of applications against the Building Rules.

A private certifier may assess a development against the Building Rules, assign a classification, require further information from the applicant, modify the application of the Building Rules, permit an applicant to vary the application, grant provisional building rules consent, with or without conditions, and may also grant a variation to the building rules consent as part of a variation of the development authorisation.

The private certifier must possess the qualifications, experience and insurance set out in the regulations. However, the private certifier may not issue a Provisional Development Plan Consent, or a Development Approval.

When a building owner engages a private certifier to assess an application and grant a provisional building rules consent, the private certifier must notify the shire/council as soon as practicable, and must notify the shire/council in writing of any decision. The private certifier must also certify that the provisional building rules consent is consistent with the provisional development plan consent, including any conditions imposed by the shire/ council.

The shire/ council will then issue a Development/ Planning Approval.

Development approval/building permitsProvided no additional information is required, the shire/council shall decide, usually within a specified time (eg. 10 days or four weeks) whether to approve or refuse an application, and notify the applicant accordingly. Where an application is approved, the shire/ council usually returns one copy of the documents (stamped or otherwise endorsed by the shire/ council or private certifier) to the applicant. If


NOTE

It is important to make sure that where Council approval is required it is obtained. Landowners and occupants can be ordered to remove unapproved fill and pay the costs of taking it to a lawful waste facility. Refer to the NSW Office of Environment & Heritage website, or the environmental department in your state or territory, for further details.


the approved building work is not commenced within a certain period (eg.12 months) or completed within a certain time span (eg. three years from the date of approval), the approval may lapse.

Dispute resolutionAn applicant for development approval may be able to appeal to a relevant Court/Authority against a refusal of an application or any conditions of approval imposed by the shire/council or private certifier. An appeal may also be lodged against an interpretation of the Building Rules, a decision by shire/council or private certifier not to grant a modification, or in the case of a dispute over a retaining wall, common wall, or any other matters set out in the Acts.

There are a number of provisions in the Acts dealing with appeals and enforcement relating to the total development approval process and some of these may apply to approval procedures for residential construction.

Notification requiredThe licensed building work contractor who is carrying out the building work, or if there is no licensed building work contractor, the building owner is required to provide the shire/council notice of the commencement and completion of the building work, and where specified by the shire/council, notice of the commencement or completion of any stage of the building work. Theses notifications can be made verbally or by telephone, or in writing, by mail, facsimile or email.

It is good practice for applicants to discuss the design of their house or alterations with their neighbours from an early stage and before any formal application is lodged with the council or accredited certifier. What individuals see as an acceptable impact can vary substantially; a positive attitude and an open mind to a neighbours’ opinion is essential to achieving a good outcome. Early discussion of plans aimed at accommodating the neighbours’ amenity can prevent conflict at a later stage.

3.4 Apply NCC classifications

Principles of classificationsThe classification of a building or part of a building is determined by the purpose for which it is designed, constructed or adapted to be used.

Class 1Class 1 buildings are not located above or below another dwelling, or another class of building other than a private garage. A sole-occupancy unit used for residential purposes located over another sole-occupancy unit used for residential purposes will always be a Class 2 or Class 3 building (depending on the circumstances). It cannot be a Class 1 building.

Class 1AA single Class 1 dwelling can be made up of more than one building. For example, it may include what is ordinarily called a house, plus one or more habitable ‘outbuildings’ such as sleepouts. (Note that a habitable building such as a sleepout cannot be classified as a Class 10 building). It also includes a row of houses, terrace houses, town houses or villa units. The height or number of storeys of a Class 1



building makes no difference to its classification. The separating wall between adjoining Class 1 dwellings must start from the ground level as illustrated in Figure 3.11 below.

Figure 3.11 Identification of Class 1 Building

(NCC Fig 1.3.2)

NOTE: For fire-resisting construction between Class 1 buildings see NCC Part 3.7.1.

Figure 3.12 Typical Class 1 Configurations

(NCC Fig 1.3.2)



Class 1BA Class 1b building is a small guesthouse, boarding house or the likewith a total area of all floors not exceeding 300m2, measured over the enclosing walls of the class1b building, in which no more than 12 persons would ordinarily be resident. Guest, boarding, or lodging houses which do not meet the criteria for a Class 1b building are classifiable as Class 3 buildings.

The Class 1b classification can attract concessions applicable to Class 3 buildings. These concessions allow people to rent out rooms in a house, or run a bed and breakfast, without having to comply with the more stringent Class 3 requirements. The reasoning is that the smaller size of the building and its lower number of occupants represents reduced fire risks.

Apart from their use, the primary difference between Class 1a and Class 1b buildings is that the latter is required to have a greater number of smoke detectors. These differences are set out in Volume 2 of the NCC.

Class 2A Class 2 building is one which contains two or more sole-occupancy units each of which is a separate dwelling. Figure 3.13 shows some configurations of Class 1 and Class 2 buildings.

Where a sole-occupancy residential unit is located above another sole-occupancy residential unit, the building containing the units can be either a Class 2 or a Class 3 building, depending on the other circumstances of the building proposal. Also, any sized building can be classified as Class 1 or Class 2 if it is used to house any number of unrelated people who jointly own or rent it, or share it on a non-rental basis with an owner or tenant.

Figure 3.13 Elevation Showing Typical Configuration of Class 1 and Class 2 Buildings (with non-combustible roof coverings

(NCC Fig A3.2(1))



Class 3Class 3 buildings is a residential building providing accommodation for unrelated people. The length of stay is unimportant. Class 3 examples include:

a boarding-house, guest house, hostel, lodging house or backpackers accommodation

the residential parts of hotels and motels;

a residential part of a school

accommodation for the aged, children or people with disabilities

a residential part of a health-care building which accommodates members of staff

a residential part of a detention centre.

An exception to this classification could include certain bed and breakfast accommodation which falls within the concession provided for Class 1b buildings. Further, it is not unusual for a managers’, owners’ or caretakers’ dwelling attached to a Class 3 building to be thought of as a Class 4 part of the Class 3 building. However, a Class 4 part of a building can only be part of a Class 5-9 building.

Accordingly, such dwellings are either classified as Class 1, Class 2 or Class 3, depending on the circumstances of the building proposal.

Class 4Class 4 classification applies to some types of accommodation located within a Class 5, 6, 7, 8 or 9 building if it is the only dwelling in the building.

A Class 4 part cannot be located within a Class 1, Class 2 or Class 3 building.

There can only be one Class 4 dwelling in a building. If there are two or more dwellings, they are Class 1, Class 2, or possibly Class 3. These Class 1, Class 2 or Class 3 parts need not be attached to one another, nor be more than a single storey.

Where a Class 4 part of a building is rented out for accommodation purposes, it retains its Class 4 classification. However, if any other part of the principal building is used for accommodation, for example, the attached shop is converted into an additional flat, both flats become classifiable as Class 2 or, depending on their use, possibly Class 3

Examples of class 4 buildings are:

a caretaker's flat within a building;

accommodation over or otherwise connected to a shop.

Class 5Class 5 buildings include an office building used for professional or commercial purposes, excluding buildings of Class6, 7, 8 or 9.



Class 6A Class 6 building is a shop or other building for the sale of goods by retail or the supply of services direct to the public, including—

(a) an eating room, cafe, restaurant, milk or soft-drink bar; or

(b) a dining room, bar area that is not an assembly building, shop or kiosk part of a hotel or motel; or

(c) a hairdresser’s or barber’s shop, public laundry, or undertaker’s establishment; or

(d) market or sale room, showroom, or service station

A service station means a garage which is not a private garage and is for the servicing of vehicles, other than only washing, cleaning or polishing. The expression ‘service station’ is not intended to cover buildings where panel beating, auto electrical, muffler replacement, tyre replacement and the like are solely carried out. Such buildings should be classified as Class 6, Class 7 or Class 8 buildings as the appropriate authority sees fit.

Class 7Class 7a is a building which is a car-park; and Class 7b is a building which is used for storage, or display of goods or produce for sale by wholesale (often referred to as a ‘warehouse’).

Class 8Class 8 is a laboratory, or a building in which a handicraft or process for the production, assembling, altering, repairing, packing, finishing, or cleaning of goods or produce is carried on for trade, sale, or gain.

The most common way to describe a Class 8 building is as a ‘factory’. However, this can give a simplistic impression of the types of building which can fall within this classification.

Class 8 examples include:

some laboratories, despite their often small size, have been included a Class 8 buildings principally because of their high fire hazard;

buildings used for altering or repairing (except service stations, which are specifically included as Class 6 buildings);

potteries;

food manufacturers (but not restaurants, which are specifically included as Class 6 buildings);

buildings used for the packing of produce.

Class 9Class 9 is a building of a public nature.

Class 9a is a health-care building, including those parts of the building set aside as a laboratory; or



Class 9a buildings are health-care buildings, including day-care surgeries or procedure units and the like. Laboratories which are part of a Class 9a building are Class 9a, despite the general classification of laboratories as Class 8 buildings.

Class 9b — an assembly building, including a trade workshop, laboratory or the like in a primary or secondary school, but excluding any other parts of the building that are of another Class; or

These buildings can include:

theatres, cinemas and halls, churches, schools, early childhood centres, kindergartens, pre-schools and child-minding centres;

indoor cricket, tennis and basketball centres;

snooker halls;

bus and railway stations.

Class 9c is an aged care building which may contain residents who have various care level needs.

The Class 9c classification recognises that many residents progress through a continuum of care needs from low to high. Many older people enter residential care with low care needs, but, as they age, require higher levels of care. In the past, such progression often necessitated the transfer of a hostel resident to a nursing home.

This frequently had negative consequences for the health and well-being of the resident, for whom the hostel accommodation was home. It also led, at times, to the separation of couples with differing care needs.

Building designers should note that Class 3 buildings include hostels for the accommodation of the aged, and Class 9a buildings include nursing homes. It is important to be aware, however, that construction of Class 3 or 9a buildings may restrict the options available to the operators of a facility in relation to the profile of the residents they wish to accommodate.

Where the potential exists for residents of varying care needs to be accommodated, consideration of the Class 9c provisions may be appropriate. The Class 9c classification allows for any mix of low and high care residents and is intended to allow the mix to change, as the residents' care needs change over time, without the need to obtain any further consent or approval from the appropriate authority.

Multi-care level facilities are for residents who may require the full range of care services outlined by the Aged Care Act. Hence, it is not intended to restrict the resident type and provides maximum flexibility for service providers, residents and the community.

Class 10Class 10 buildings are non-habitable buildings or structures. There is no requirement for Class 10 buildings to be appurtenant2 to a building of any other class. 2 Appurtenances is a term for what belongs to and goes with something else, with the appurtenance being less significant than what it belongs to. In a legal context, an appurtenance could for instance refer to a back-yard that goes with the adjoining house. The idea being expressed is that the back-yard "belongs" to the house, which is the more significant of the two.



For example, a small shed standing on its own on an allotment and a toilet block in a park.

A habitable ‘outbuilding’ which is appurtenant to another building is generally part of that building. Again, habitable ‘outbuildings’ cannot be classified as Class 10 buildings.

Class 10a buildings are non-habitable buildings being a private garage, carport, shed, or the like. See Figure 3.14 for an indication of some Class 10 building configurations

Class 10b structures are structures being a fence, mast, antenna, retaining or free-standing wall, swimming pool, or the like.

Other Class 10b examples include a detached entertainment room on the same allotment as a Class 1 building, perhaps associated with a swimming pool.

Class 10c buildings are Bushfire shelters/bunkers.

Figure 3.14 Domestic Allotment – Classification of Buildings and Structures

NOTE: A Class 10 building may be attached to a Class 1 building; A Class 1 building may consist of one or more buildings (eg detached bedrooms).


http://bca.saiglobal.com/Script/Content/viewer/document/FindPage.asp?docID=1691&hist=yes&anchorID=Vol2/Swimming_pool#Swimming_pool


The following diagram summarises the 10 NCC classes:

Figure 3.15 Summary of NCC Classes

(Source: Tyrrell, 2006)

3.5 NCC Classification issuesThere are often small differences between classes and it is necessary to consider what is the most likely use of the building. To assist with NCC classification issues, some examples of difficult classifications are included in Appendix A below.

3.6 ConclusionThis chapter has introduced you to the building classification system in Australia and provides you with the information central to applying the National Construction Code (NCC) to the projects you are working on. In Chapter 4 you will look at specific energy efficiency measures and detail from the NCC.



4 Mandatory performance requirements in low-rise construction

This chapter expands upon the theory from the first three chapters and introduces you to some of the mandatory performance requirements of the National Construction Code. The key areas covered include energy efficiency of the building, the services that support it, and the ‘star rating’ of the completed project. In addition, it is important that you are competent in addressing lighting and ventilation requirements as these can have a significant impact on the well-being of occupants, as well as affecting the amount of energy used in the dwelling.

4.1 Applying the national construction codeTo successfully construct low-rise buildings requires a thorough knowledge of the purpose and content of the NCC coupled with the ability to interpret other codes and standards related to a specific building. Some relevant construction methods and practices are outlined here.

An important part of construction is understanding both the regulations, codes and standards as well as the client expectations from the project. Where a client is seeking to construct with sustainability features, builders can add value by knowing about design as well as being able to add commentary on key products.

Builders should consult with clients and assist in the design process wherever possible.

4.2 Low-rise construction – energy efficiencyThere are three mandatory performance requirements for energy efficiency listed in the BCA Volume Two.


TIP

Room location can play an important part in a buildings performance (YourHome 2008)

The north side is warmer in winter and the best place for rooms you use a lot, like living areas.

The west side gets hot in the afternoon and is best for rooms you don't use often, like bathrooms, garages and laundries.

The south side is the coolest and good for bedrooms in warmer climates, as well as rooms you don't use often.

The east side gets morning sun and is good for breakfast rooms, kitchens and bedrooms


P2.6.1 BuildingA building must have, to the degree necessary, a level of thermal performance to facilitate the efficient use of energy for artificial heating and cooling appropriate to—

(a) the function and use of the building; and

(b) the internal environment; and

(c) the geographic location of the building; and

(d) the effects of nearby permanent features such as topography, structures and buildings; and

(e) solar radiation being—

(i) utilised for heating; and(ii) controlled to minimise energy for cooling; and

(f) the sealing of the building envelope against air leakage; and

(g) the utilisation of air movement to assist cooling.

P2.6.2 ServicesTo the degree necessary—

(a) have features that facilitate the efficient use of energy appropriate to—

(i) the domestic service and its usage; and(ii) the geographic location of the building; and(iii) the location of the domestic service; and(iv) the energy source; and

(b) obtain heating energy from—

(i) a source that has a greenhouse gas intensity that does not exceed 100 g CO2-e/MJ of thermal energy load; or(ii) a source that is renewable on-site such as solar, geothermal or wind; or(iii) another process as reclaimed energy.

(Domestic Services are the basic engineering systems of a house that use energy, or control the use of energy, and includes heating, air-conditioning, mechanical ventilation and hot water systems but excludes cooking appliances or portable appliances.)


TIP

Even if your home is well-insulated, heated or cooled air can leak in and out through gaps and cracks and even exhaust fans. By cutting down on draughts you can save up to 25 per cent of your heating and cooling bills.

(www.livingreener.org.au)


House energy rating using computer simulation for a particular design of a REFERENCE BUILDING as evidence of suitability.

Table 4.5 BCA Application of Energy EfficiencyState/Territory 3.12 Energy Efficiency – State territory Appendix 7

ACT AppliesNSW Class 1 & 10 subject to BASIX and NSW Appendix for the BCA

2009NT Replaced with BCA 2009 Part 3.12QLD AppliesSA Applies 1st May 2010 for commercial and 1st Sept 2010 for

residentialTAS Replaced with BCA 2009 Part 3.12VIC Replaced with BCA 2009 Part 3.12WA Replaced with BCA 2009 Part 3.12

4.3 Six Star energy ratingIncreased energy efficiency requirements for all new dwellings built in Australia will come into effect and apply to both commercial and residential constructions as determined and implemented by each state/territory on a rolling basis. As at 2012 relevant requirements are set out in Table 4.5 above.

The new ‘6-star’ energy efficiency requirement – which also applies to alterations or additions to existing homes – replaces the previous 5-star energy efficiency requirement which had been in place since 2006.

There are two options for complying with the energy efficiency Deemed-to-Satisfy Provisions for the following energy efficiency factors:

3.12.1 – Building Fabric3.12.2 – External glazing3.12.3 – Building sealing3.12.4 – Air movement3.12.5 - Services

Option 1To achieve the required star rating to the Nationwide House Energy Rating Scheme and in addition, comply with the BCA for energy saving features not covered by the scheme such as the testing and installation of insulation, thermal breaks, compensation for downlights, floor edge insulation and detailed provisions for building sealing.

Option 2To satisfy all the detailed provisions including meeting the Total R-Values of roofs, walls and floors, the glazing allowances and the air movement requirements. These detailed provisions also include the testing and installation of insulation, thermal breaks, compensation for downlights, floor edge insulation and detailed provisions for building sealing.

This is explained in the flow chart in Figure 4.16.



Figure 4.16 Six Star Energy Rating Process Diagram

There are several computer-based energy efficiency rating programs (such as BASIX, FirstRate5, AccuRate or BERSPro) that can assess a building for star rating to 6 stars or better.



The prescriptive measures contained in the National Construction Code (NCC) include different levels of insulation for various building elements (walls, floor and roofs) for different climate zones, and restrictions on the amount and type of glazing in an external wall.

The area of glass is limited based on the amount of shading provided and the orientation of the wall. A house with no eaves and no additional shading to the windows is required to have less glazed area than a house with eaves. Good shading of windows (such as eave overhangs) and good orientation of the house (so that the main windows to living areas are facing due north) will enable the new requirements to be met for minimal cost (a few hundred dollars for more efficient insulation).

Table 4.6 Shading TipsOrientation Suggested Shading Type

North Fixed or adjustable shading placed horizontally above windowEast & West Adjustable vertical screens outside windowNE & NW Adjustable shadingSE & SW Planting

(YourHome 2008)

Good design, including thoughtful consideration of the orientation of the home, will help meet the 6 star efficiency requirements and over the long term will lead to a reduction in energy-use costs. The increased energy efficiency requirements for housing - along with new energy efficiency requirements for commercial buildings - will help in meeting Australia's target to increase energy efficiency in dwellings by 10 percent within 10 years.

Heating and cooling loads – Classes 1 and 10To reduce heating or cooling loads, a building must have an energy rating to the Nationwide House Energy Rating Scheme using a calculation method that complies with the ABCB Protocol for House Energy Rating Software of not less than—

(i) 6 stars; or(ii) for a building in climate zones 1 or 2, 5.5 stars if the building has an outdoor living area as described in (B) if the outdoor living area—

(A) is fully covered with an impervious roof having a Total R-Value of at least 1.5 (for downward heat flow); or

(B) has at least one permanently installed ceiling fan; or


TIP

With good orientation the need for auxiliary heating and cooling is reduced, resulting in lower energy bills and reduced greenhouse gas emissions.

(YourHome 2008)


(iii) for a building in climate zones 1 or 2, 5 stars if the building has an outdoor living area and if the outdoor living area is fully covered with an impervious roof having a Total R-Value of at least 1.5 (for downward heat flow) and has at least one permanently installed ceiling fan.

This outdoor living area is a space that-

(i) is directly adjoining, and directly accessible from, a general purpose living area of a Class 1 building such as a lounge, kitchen, dining or family room, which is not a room for sleeping or specialist tasks such as a study or home theatre; and(ii) has a floor area of not less than 12.0 m2; and(iii) has length and width dimensions of not less than 2.5 m each; and(iv) has an opening height above floor level of not less than 2.1 m; and(v) has one side permanently open with a second side either—

(A) permanently open; or(B) readily openable.

Heading and cooling loads – Classes 2-9Performance requirements

A building, including its services, must have, to the degree necessary, features that facilitate the efficient use of energy appropriate to—

(a) the function and use of the building and services; and(b) the internal environment; and(c) the geographic location of the building; and(d) the effects of nearby permanent features such as topography, structures and buildings; and (e) solar radiation being—

(i) utilised for heating; and(ii) controlled to minimise energy for cooling; and

(f) the sealing of the building envelope against air leakage; and(g) the utilisation of air movement to assist heating and cooling; and(h) the energy source of the services.

A building, including its services, must have, to the degree necessary, features that facilitate the maintenance of systems and components appropriate to the function and use of the building.

Heating such as for a conditioned space must, to the degree necessary, obtain energy from—

(a) a source that has a greenhouse gas intensity that does not exceed 100g CO2-e/MJ of thermal energy load; or

(b) a source that is renewable on-site such as solar, geothermal or wind; or(c) another process as reclaimed energy.



Verification using a reference buildingFor a Class 3, 5, 6, 7, 8 and 9 building, compliance with these performance requirements are verified when it is determined that the annual energy consumption of the proposed building with its services are not more than the annual energy consumption of a reference building3 when—

(i) the proposed building is modelled with the proposed services; and(ii) the proposed building is modelled with the same services as the reference building.

The annual energy consumption of the proposed building as described above may be reduced by the amount of energy obtained from—

(i) a source that is renewable on-site such as solar, geothermal or wind; or(ii) another process as reclaimed energy.

The annual energy consumption calculation method must comply with the ABCB Protocol for Building Energy Analysis Software

Complying new homes and extensionsUnder the various Building/Development Acts and Regulation in each state/territory, approval for a development is required from the shire/council for all building work to ensure it complies with the NCC or the state/territory equivalent code. In NSW, projects are most likely to require a BASIX certificate (see BASIX below).

Before this approval can be issued, either the shire/council or a private certifier must assess the design of new homes and extensions including checking the design for compliance with the 6-star energy efficiency requirements.

If the energy efficiency of the home has been rated using a computer-based energy rating program, a printed verification report, signed and dated by the house energy rater who did the assessment, with all supporting documentation must be submitted to the Shire/Council or private certifier for verification.

A house energy rating can be completed by any person with the necessary software and skills, including an architect, building designer, builder or building surveyor.

BASIX (NSW)BASIX is required for all developments which contain new residential dwellings or alterations and additions to a dwelling. . A dwelling is defined as 'a room or suite of rooms occupied or used or so constructed or adapted as to be capable of being occupied or used as a separate domicile'

Use of heavy drapes and pelmets to achieve the 6-star requirementsAttaining a star rating with the use of heavy drapes and pelmets cannot be used for compliance with the Building Rules if there is any doubt about the installation taking place. Software tools such as FirstRate5, BERSPro and AccuRate are valid assessment programs. FirstRate5 and AccuRate only allow for the use of Holland Blinds on glazing to be included as part of the building shell.

A house energy rater are usually required to register with the state/territory controlling authority on the Register of House Energy Rating Assessors. These raters must agree to comply with a Code of Practice and can undertake energy rating assessments as an ‘independent technical expert’. If a house energy 3 Reference building means a hypothetical building that is used to calculate the maximum allowable annual energy load, or maximum allowable annual energy consumption for the proposed building.



rating has been verified by an ‘independent technical expert’, this must be accepted by the Council or private certifier

Designing and constructing an energy efficient homeHouse location – Climate ZonesThe manner in which the energy efficiency requirements are achieved will depend upon the severity of the ‘climate zone’ in which a house is located. Climate zones are based on climatic data and are generally aligned with local government boundaries.

There are eight climate zones across Australia:

Climate Zone 1 (covering across the top of Australia)

Climate Zone 2 (covering the coastal areas from Mackay to Coffs Harbour)

Climate Zone 3 (covering across the upper middle of Australia)

Climate Zone 4 (covering across the lower middle of Australia)

Climate Zone 5 (covering WA and SA and Newcastle coastal fringes)

Climate Zone 6 (covering the South West WA, South East SA and the Victorian coast ).

Climate Zone 7 (covering most of Tasmania, and the high country in Vic & NSW)

Climate Zone 8 (covering the alpine regions in Tas, Vic and NSW)

The climate zone map is available from the ABCB (see chapter 1 for climate zone map).

NCC Deemed-to-satisfy provisions – Building fabric



The design and construction of the house’s envelope—roof, external walls and floors—will have an effect on the thermal comfort of a house.

The provisions for building fabric include:

Thermal insulation

Roofs

Roof lights

External walls

Floors

Attached Class 10a buildings

The building envelope must be designed to have effective resistance to heat flow and it may be either into or out of the building. In the southern part of Australia (climate zones 4-8), the NCC considers the heat flow upwards from the building is the predominant energy user in the winter months when our houses are being warmed while in the hotter climates (Climate zone 1 & 2) it might be heat flow downwards requiring more energy to overcome.

Hence a thermally efficient building envelope means less energy to artificially heat or cool a building. Peak demand (air conditioning in summer) is not a current priority although consideration is being given requiring this in our design of dwellings.

Thermal insulationAll materials have a measured thermal resistance which is known as the R-value. The R-values of all the components of a wall system added together gives the total R-value.

The NCC requires a minimum R-value be attained for walls (based on the climate zone) and with brick veneer and weatherboard houses this will require the addition of insulation. Most cavity and solid masonry walls do not require additional insulation. Brick veneer and weatherboard external walls must be insulated with bulk insulation or reflective foil.

Insulation must be installed to form a consistent and continuous barrier (other than at studs) and any gaps in the barrier allow heat in or out thereby reducing the efficiency of the barrier. Any insulation must not interfere with the operation of services such as electrical switches and downlights.

Where a reflective insulation is to be used it is important to ensure that the required airspace is provided adjacent to the reflective surface.



Table 4.7 Thermal Conductivity of Typical Wall, Roof/ceiling, and Floor MaterialsMaterial Description Material

density kg/m3

Thermal conductivity W/m.K

1 Framinga) Steel 7850 47.5b) Timer – kiln dried hardwood (across the grain) 677 0.16c) Timber – Radiata pine (Across the grain) 506 0.102 Roof Claddinga) Aluminium sheeting 2680 210b) Concrete or terrra cotta tiles 1922 0.81c) Steel sheeting 7850 47.53 Wall Claddinga) Aluminium sheeting 2680 210b) Autoclaved aerated concrete 350 0.10

900 0.27c) Cement render (1 cement : 4 sand) 1570 0.53d) (i) Clay brick 2.75kg

(ii) Clay brick 3.25kg (iii) Clay brick 3.75kg

143016901950

0.550.650.78

e) Concrete blocks(iv) 190 mm dense or 90 mm dense solid(v) 140 mm dense or 190 mm lightweight(vi) 90 mm dense hollow or 90 mm lightweight solid(vii) 1400mm lightweight(viii) 90mm ligtweight

1100/22001250/9101650/180010501360

1.10.80.750.670.55

f) Fibre cement 1360 0.25g) Gypsum plasterboard 880 0.17h) Pine weatherboards 506 0.10i) Plywood 530 0.14j) Solid concrete 2400k) Steel sheeting 7850 47.5l) Prestressed hollow core concrete panel 1680 0.804 Flooring materialsa) Carpet underlay - 0.04b) Carpet - 0.05c) Prestressed hollow core concrete planks 1680 0.80d) Particleboard 640 0.12e) Plywood 530 0.14f) Timber – kiln dried hardwood (across the grain) 677 0.16g) Timber – Radiata pine (across the grain) 506 0.10h) Solid concrete 2400 1.44i) Vinyl floor tiles 2050 0.795 Other Materialsa) Air (still) 1.2 0.03b) Clay soil (10% moisture content) 1300 0.6c) PMMA (polymethylmethacrylate) 1180 1.00d) Polycarbonates 1200 0.2e) Sand (6% moisture content) 1800 1.64f) Soda lime glass 2500 1.0



Roofs/CeilingsBoth tiled and metal roofs must be insulated as the roof is the major source of heat gain or loss. Insulation must be placed under the roof or above the ceiling and must be continuous and overlapped in some cases.

One option is the installation of insulation batts—although a combination of bulk insulation and reflective foil can be installed. The construction of a roof or roof and associated ceiling, must achieve the minimum required Total R-Value as specified.

Table 4.8 Roof and Ceiling - Minimum Total R-value Climate Zone 1 2 3 4,5 6,7 8

Altitude4 <300m

Altitude >300m

Direction of heat flow D5 D D&U D&U U U UMinimum Total R-Value for a roof with an upper surface solar absorptance value of not more than 0.4

4.1 4.1 4.1 4.1 4.1 4.1 6.3

Minimum Total R-Value for a roof with an upper surface solar absorptance value of more than 0.4 but not more than 0.6

4.6 4.6 4.6 4.6 4.6 4.6 6.3

Minimum Total R-Value for a roof or ceiling with a roof upper surface solar absorptance value of more than 0.6

5.1 5.1 5.1 5.1 5.1 5.1 6.3

(NCC Table 3.12.1a)

Solar absorptance valuesA light coloured roof reduces the flow of heat from solar radiation better than a dark colour roof. A roof with a solar absorptance value of less than 0.55 means the roof is of a light colour such as white, off-white, cream or dull zinc aluminium. Typical absorptance values based on ASTM6 E903 are detailed in Table 4.9.

Table 4.9 Solar Absorptance valuesRoof Colour Solar Absorptance Value

Slate (Dark Grey) 0.90Red, Green 0.75Yellow, buff 0.60Zinc Aluminium – dull 0.55Galvanised steel – dull 0.55Light Grey 0.45Off White 0.35Light Cream 0.30

4 Altitude means the height above the Australian Height Datum at the location where the building is to be constructed5 Note: U = upwards; D = downwards6 American Society for Testing and Materials - ASTM International



Table 4.10 Total R-value for typical roof and ceiling construction Roof construction description Total R-value

a) Flat roof, skillion roof and cathedral ceiling – ceiling under rafter Ventilated Down 0.48Up 0.36

b) Flat roof, skillion roof and cathedral ceiling – exposed rafters Unventilated Down 0.44Up 0.38

c) Pitched roof with flat ceiling – tiled roof Ventilated Down 0.74Up 0.23

Unventilated Down 0.56Up 0.41

d) Pitched roof with flat ceiling – metal roof Ventilated Down 0.72Up 0.21

Unventilated Down 0.54Up 0.39

(NCC Fig 3.12.1.1)

Notes:

1. The Total R-value of the roof and ceiling construction in Table 4.10 is based on there being a roof space. If the roof space is filled, the roof space R-Value needs to be subtracted from the Total R-Value of the roof and ceiling materials.

2. The Total R-Value of the unventilated roof and ceiling construction in Table 4.10 for tiled roofs are based on there being sarking-type material which would prevent ventilation of the roof space through the gaps in the roof tiles

A roof or roof and associated ceiling is deemed to achieve the minimum required Total R value specified above if it complies with the regulations outlined in Table 4.11.



Table 4.11 R-values for insulation of roofs and roofs and associated ceilingsRoof/ceiling Total R-

value of roof

materials

Minimum required Total R-

value

Minimum added R-value of

insulation

Required added bulk

insulation

Reference

Climate Zone 4Flat roof, skillion roof and cathedral ceiling – unventilated roof space

Ceiling lining under rafters

Tiled roof (clay or concrete)

0.37 3.5 3.13 R3.5 R3

Metal roof 0.35 3.5 3.15 R3.5 R3Ceiling lining on top of rafters


0.37 3.5 3.13 R3.5 R4

Metal roof 0.35 3.5 3.15 R3.5 R4Pitched roof with flat ceiling – ventilated roof space

Horizontal ceiling Tiled roof (clay or concrete)

0.22 3.5 3.28 R3.5 R2

Metal roof 0.20 3.5 3.3 R3.5 R1Pitched roof with flat ceiling – unventilated roof space


0.40 3.5 3.10 R3.5 R2

Metal roof 0.38 3.5 3.12 R3.5 R1Climate Zone 5

Flat roof, skillion roof and cathedral ceiling – unventilated roof spaceCeiling lining under rafters


0.37 3.2 2.83 R3.0 R3

Metal roof 0.35 3.2 2.85 R3.0 R3Ceiling lining on top of rafters


0.37 3.2 2.83 R3.0 R4

Metal roof 0.35 3.2 2.85 R3.0 R4Pitched roof with flat ceiling – ventilated roof space


0.22 3.2 2.98 R3.0 R2

Metal roof 0.20 3.2 3.0 R3.0 R1Pitched roof with flat ceiling – unventilated roof space


0.40 3.2 2.8 R3.0 R2

Metal roof 0.38 3.2 2.82 R3.0 R1

Table 4.12 Adjustment of minimum R-value for loss of ceiling insulationPercentage of ceiling

area uninsulatedMinimum R-value of ceiling insulation required to satisfy

2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 Adjusted minimum R-value of ceiling insulation required to compensate for loss of

ceiling area insulation0.5% to less than 1.0% 2.8 3.4 4.0 4.7 5.4 6.2 6.91.0% to less than 1.5% 2.9 3.6 4.4 5.2 6.1 7.01.5% to less than 2.0% 3.1 3.9 4.8 5.8 6.82.0% to less than 2.5% 3.3 4.2 5.3 6.52.5% to less than 3.0% 3.6 4.6 5.9 Not permitted3.0% to less than 4.0% 4.2 5.74.0% to less than 5.0% 5.0

5.0% or more

Note: Where the minimum R-value of ceiling insulation required to satisfy NCC is between the values stated, interpretation may be used to determine the adjusted minimum R-value.



Roof lights

Roof lights provide a point of heat transfer and as such their affect on the overall thermal performance of the house must be limited. All roof lights where the aggregate area of no more than 3% of the floor area must be fitted with transparent elements/ceiling diffusers that demonstrate high thermal performance. The total area of roof lights serving habitable rooms and connected spaces such as corridors is restricted and there are maximum allowable thermal values for roof lights.

External walls

External walls must achieve a minimum R-value. An external wall must satisfy one of the tabulated options except for opaque non-glazed openings in external walls such as doors (including garage doors), vents, penetrations, shutters and the like; and glazing openings complying with the External Glazing requirements.

Where an option is used that requires the external wall to achieve a surface density of 220kg/m2, the following forms of construction achieve the required surface density -

(i) two leaves of 90mm thick or greater clay or concrete masonry; or (ii) 140mm thick or greater dense-weight hollow concrete or clay blocks with 10mm or greater

plasterboard or render; and at least one concrete grouted horizontal bond beam; and vertical cores filled with concrete grout at centres not exceeding 1000mm; or

(iii) 140mm thick or greater concrete wall panels and dense weight hollow concrete or clay blocks with all vertical cores filled with concrete grout; or

(iv) 190mm thick or greater dense-weight hollow concrete or clay blocks with at least one concrete grouted horizontal bond beam; and vertical cores filled with concrete grout at centres not exceeding 1800mm; or

(v) Earth-wall construction with a minimum wall thickness of 200mm.

In climate zones 4 and 6, where the minimum required Total R-Value specified cannot be achieved by the external walls of a storey, the deficit may be compensated by the performance of the glazing in that storey.

A wall that is required to achieve a minimum Total R-Value; and

has lightweight external cladding such as weatherboards, fibre cement or metal sheeting fixed directly to the metal frame and;

has a wall lining that is fixed directly to the metal frame,

must have a thermal break consisting of a material with an R-value of not less than 0.2 installed between the metal frame and the external cladding. A thermal break may be provided by materials such as timber of not less than 20mm thickness, expanded polystyrene strips of not less than 12mm thickness or plastic strips that achieve the required R-Value.



Table 4.13 Options for each part of an external wall Climate

Zone Options

1,2, 3, 4 & 5

a) Achieve a minimum Total R-value of 2.8

b) i) Achieve a minimum Total R-value of 2.4 andii) Shade the external wall of the storey with a verandah, balcony, eaves, carport or

the like, which projects at a minimum angle of 15 degrees in accordance with BCA Figure 3.12.1.2

6 & 7 Achieve a minimum Total R-value of 2.88 Achieve a minimum Total R-value of 3.8

(NCC Table 3.12.1.3a)



Table 4.14 Options for each part of an external wall with a surface density of not less than 220kg/m2Climate

Zone Options

1,2, &3 a) i) For a storey, other than one with another storey above, shade the wall with a verandah, balcony, eaves, carport or the like which projects at a minimum angle of 15 degrees in accordance with NCC

ii) when the external walls are not shaded in accordance with (i) and there is another storey above, external glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 20%; and

iii) the external wall incorporates insulation with an R-Value of not less than 0.5; and 2iv) The lowest storey containing habitable rooms has –

A) a concrete slab on the ground floor; orB) masonry internal walls

5 a) i) For a storey, other than one with another storey above, shade the wall with a verandah, balcony, eaves, carport or the like which projects at a minimum angle of 15 degrees in accordance with NCC

ii) when the external walls are not shaded in accordance with (i) and there is another storey above, external glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 15%; and

iii) the external wall incorporates insulation with an R-Value of not less than 0.5; and iv) The lowest storey containing habitable rooms has –


b) i) Shade the external wall of the storey with a verandah, balcony, eaves, carport or the like, which projects at a minimum angle of 15 degrees in accordance with NCC

ii) External glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 15%; and

iii) The lowest storey containing habitable rooms has –A) a concrete slab on the ground floor; orB) masonry internal walls

4 & 6 a) i) The external glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 15%; and

ii) the external wall incorporates insulation with an R-Value of not less than 0.5; and iii) The lowest storey containing habitable rooms has –


b) External glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 20%

c) i) The external wall incorporates insulation with an R-Value of not less than 1.0; andii) The lowest storey containing habitable rooms has –


7 a) i) The external glazing complies with the NCC with the applicable value for CSHGC in the NCC reduced by 15%; and

ii) the external wall incorporates insulation with an R-Value of not less than 1.0; andb) i) External glazing complies with the NCC with the applicable value for CSHGC in the NCC

reduced by 20%; andii) the external wall incorporates insulation with an R-Value of not less than 0.5

c) The external wall incorporates insulation with an R-Value of not less than 1.5.

8 Achieve a minimum Total R-value of 3.8



Wall shadingEaves and other projections affect the way that the external wall absorbs or conducts heat.

Figure 4.17 Measurement of a projection for wall shading

(NCC Fig 3.12.1.2)

External wall constructionTable 4.15 Total R-value for typical wall constructionExternal wall construction description Total R-

valuea) Weatherboard

0.48

b) Fibre cement sheet0.42

c) Clay masonry veneer0.56



d) Concrete blockwork masonry0.54

e) Cavity clay masonry0.69

f) Externally insulated clay masonry0.53

g) Externally insulated concrete masonry0.46

h) Autoclaved aerted concrete masonry2.42



Table 4.16 Reflective airspace detailsWall construction Reflective airspace details R-value

added by reflective insulation

Concrete or masonry with internal plasterboard on battens

One 20mm reflective airspace located between reflective insulation (of not more than 0.05 emittance inwards) and plasterboard

0.48

External wall cladding (70mm timber frame with internal lining)

One 70mm reflective airspace located between reflective insulation (of not more than 0.05 emittance inwards) and plasterboard

0.43

Masonry veneer (70mm timber frame with internal lining)

a) One 70mm reflective airspace located between reflective insulation and plasterboard; and

0.95

b) One 25 mm anti-glare airspace located between reflective insulation (of not more than 0.2 emittance outwards) and masonry

Cavity masonry a) No airspace between the reflective insulation and the inner leaf of masonry; and

0.50

b) One 35mm anti-glare airspace located between reflective insulation (of not more than 0.2 emittance outwards) and the outer leaf of masonry

Suspended floorsThere are separate requirements for suspended timber or concrete floors and slab on ground floors with an in-built heating or cooling system.

Slab on ground floors with no heating or cooling are thermally efficient and no additional thermal efficiency is needed. In fact, slab floors have a certain thermal mass that can be used to keep a room cool in summer, or add heat in winter.

Figure 4.18 Thermal Mass Winter Summer

(YourHome 2008)

A concrete slab-on-ground with an in slab heating or cooling system must have insulation installed around the vertical edge of its perimeter. The insulation must have an R-Value not less than 1.0; be water resistant; and be installed to a minimum depth of 300 mm below ground level.

An under tile or in-screed heating system is not considered to be an in-slab heating system.



Table 4.17 Suspended floor - Minimum Total R-value

Climate Zone1 2 3 4 5 6 7 8

Direction of heat flow

Upwards Downwards

Minimum Total R-value 1.5 1.0 1.5 2.25 1.0 2.25 2.75 3.25

(NCC Table 3.12.1.4)

Table 4.18 Total R-value for typical suspended floor construction7

Enclosure and height of floor Direction of heat flow

Total R-valueCavity

masonry190mm

concrete masonry

Single skin masonry

9mm fibre cement sheet

a) Suspended Timber FloorEnclosed – not more than 0.6m high

Upwards 1.00 0.93 0.88 0.77Downwards 1.11 1.06 1.01 0.90

Enclosed – more than 0.6m high but to no more than 1.2m high


Enclosed – more than 1.2m high to not more than 2.4m high


Unenclosed Upwards 0.39 0.39 0.39 0.39Downwards 0.51 0.51 0.51 0.51

b) Suspended concrete floorEnclosed – not more than 0.6m high


Enclosed – more than 0.6m high but to no more than 1.2m high


Enclosed – more than 1.2m high to not more than 2.4m high


Unenclosed Upwards 0.34 0.34 0.34 0.34Downwards 0.46 0.46 0.46 0.46


Note: The height of the floor is measured from the ground surface to the underside of the floor of the insulation.

Figure 4.19 Insulation of a slab edge

7 for a floor without a floor heating system



Attached Class 10A buildingsThe design and construction of garages and conservatories must not compromise the level of energy efficiency achieved by the house. This requires the garage or conservatory to be:

constructed to meet the same energy efficiency as the house, or

separated from the house by construction that meets the energy efficiency requirements, or

enclosed by masonry walls (other than glazed openings and doors) and be separated from the house with a masonry wall that extends to the ceiling in climate zones 4 and 5.

achieve a Total R-Value in the roof equivalent to that required for a Class 1a building

not have a garage door facing the east or west orientation other than if the Class 1 building glazing complies with NCC glazing with the applicable value for CSHGC reduced by 15%.

Figure 4.20 Attached Class 10A buildings

External glazingThe selection of the type of window and its associated glazing will provide large efficiencies in the thermal performance of the building. The extent of the shading over a window will also have a positive affect. The NCC addresses both the glass and the shading.

Standard aluminium or timber windows and doors with clear glass may be used; however the percentage of glazing area to total floor area will be limited.

The percentage of glazing area can be increased by:



selecting glazing with higher level of thermal performance (such as toned, or solar control glass or double glazing); and/or

fitting permanent or adjustable external shading devices. Shading can be provided with eave overhangs (including gutters), verandahs, pergolas or external blinds and canopies.

When using the D-T-S provisions of the NCC it is necessary to calculate the allowed values for glazing and the actual values for glazing. The actual values must not exceed the allowed values. The orientation of a window affects the overall thermal value of the glazing.

Table 4.19 Indicative ranges of whole glazing element performance values

Glass description

CommentAluminium framing Timber or uPVC framing

Total U-value range

SHGC range

Total U-value range

SHGC range

Single (monolithic or laminated)Clear Minimal variation in glass U-Value

and SHGC for different glass thicknesses

7.9 – 5.5 0.81 – 0.64 5.6 – 4.3

0.68 – 0.47

Tinted Glass SHGC depends on glass thickness and type of tint

7.9 – 5.6 0.65 – 0.33 5.6 – 4.3

0.61 – 0.25

Coated Glass U-value and SHGC depend on coating type

7.8 – 3.8 0.68 – 0.36 5.5 – 2.9

0.64 – 0.27

Tinted & Coated

Glass U-value depends on coating type. Glass SHGC depends on coating type, type of tine and glass thickness

7.8 – 3.8 0.45- 0.31 5.5 – 3.1

0.42 - 0.23

DoubleClear Glass U-value depends on cavity

width6.2 – 3.1 0.72 – 0.63 3.8 –

2.50.68 – 0.47

Tinted Glass U-value depends on caity width. Glass SHGC depends on type of tint, tinted glass thickness and on cavity width

6.2 – 3.1 0.57 – 0.36 3.8 – 2.5

0.57 – 0.27

Coated Glass U-value depends on cavity width and type of coating. Glass SHGC depends on type of coating and cavity width

6.1 – 2.4 0.60 – 0.22 3.8 – 2.1

0.59 – 0.17

Tinted & Coated

Glass U-value depends on cavity width and type of coating. Glass SHGC depends on type of coating, tinted glass thickness and cavity width.

6.1 – 2.5 0.41 - 0.21 3.8 – 2.1

0.37 – 0.16


Note:

Solar Heat Gain Coefficient (SHGC) means the fraction of incident irradiance on glazing or a roof light that adds heat to a building’s space.


Table 4.20 Worst case whole glazing element performance values

Glass descriptionAluminium framing Timber or uPVC framing

Total U-value range SHGC range Total U-value range SHGC rangeSingle clear 7.9 0.81 5.6 0.77Tinted single 7.9 0.65 5.6 0.61Clear double (3/6/3) 6.2 0.72 3.8 0,68

Figure 4.21 Method of measuring P and H in glazing calculations

Note:

1) An external shading device that complies with 3.12.2.2(b) is considered to achieve a P/H value of 2.00

2) 2) Where G exceeds 500mm, the value of P must be halved.



Building sealingExternal doors, chimneys and flues, exhaust fans and evaporative cooler outlets are a source of heat loss in cold weather. To reduce this heat loss:

draught protection strips must be fitted to the bottoms of all external swing doors

dampers or flaps that can be closed must be installed to all chimneys and flues

a sealing device or self-closing damper must be fitted to exhaust fans

a self-closing damper must be fitted to evaporative cooler outlets.

Sealing devices are not required if ventilation is necessary for the safe operation of a gas appliance.

Air movementAll habitable rooms (bedrooms and living areas) must be ventilated. The number of opening windows and the circulation of air must be considered for each habitable room.

The area of opening windows may be reduced if a ceiling fan or evaporative cooler is installed to improve circulation.

Table 4.21 Provision for air movement

Climate Zone

Minimum total ventilation opening area per habitable room (percentage of the area of the floor of the habitable room)

Without a ceiling fan or evaporative cooler

With a ceiling fan With an evaporative cooler

1 10% 7.5% 10% (see Note)2 10% 7.5% 10% (see Note)3 10% 7.5% 7.5%4 10% 5% 5%5 7.5% 5% 7.5% (see Note)

6,7 & 8 As required by Part 3.8.5

Note: Because evaporative coolers are less effective than ceiling fans in more humid locations, the requirement for ventilation opening in Climate Zones 1,2 & 5 with an evaporative cooler is the same as without one.

Ventilation openings and breeze pathsIn climate zones 1, 2, 3, 4 and 5, the total ventilation opening area required by Table 4.21to a habitable room must—

(i) be connected by a breeze path to another ventilation opening in another room or space; or


TIP

Even if a home is well-insulated, heated or cooled air can leak in and out through gaps and cracks and even exhaust fans. By cutting down on draughts it is possible to save up to 25 per cent of a homes heating and cooling bills. Weather sealing - or draught proofing - a home is one of the easiest and cheapest ways of lowering energy costs.

(www.livinggreener.org.au)


(ii) be provided by a minimum of two ventilation openings located within the same habitable room, with each ventilation opening having an area of not less than 25% of the area.

A breeze path required must—

(i) pass through not more than two openings in the internal walls with each opening having an area of not less than 1.5 m2; and

(ii) have a distance along the breeze path between ventilation openings of not more than 20m.

Figure 4.22 Breeze Pathways in Domestic Dwelling

(Source: NCC)

ServicesCeiling fans and evaporative coolersCeiling fans or evaporative coolers required to comply must—

(a) be permanently installed; and

(b) have a speed controller; and

(c) for ceiling fans, serve the whole room, with the floor area that a single fan serves not exceeding

i. 15m2 if it has a blade rotation diameter of not less than 900 mm; and

ii. 25m2 if it has a blade rotation diameter of not less than 1200 mm

Insulation of hot water and air conditioner ductworkIt is important to understand the NCC requirements around insulating hot water services and air conditioning ductwork because this can affect the dwelling being passed by the certifier. It is also important to understand what this means to the occupiers of a dwelling as incorrect installation will most likely mean higher energy bills.


http://bca.saiglobal.com/Script/Content/viewer/document/FindPage.asp?docID=1691&hist=yes&anchorID=Vol2/Ventilation_opening#Ventilation_opening


Hot water service pipes will need to be fitted with insulation to improve their efficiency. Air conditioner heating and cooling ductwork will also need to be insulated.

Heating and cooling ductwork and fittings that is not located within the insulated building envelope (including a service riser within the conditioned space, internal floors between storeys and the like), heating and cooling ductwork and fittings must - achieve the minimum required Total R-value, using thermal insulation material in accordance with AS/NZS 4859.1, and be sealed against air loss.

Where duct insulation is located under a suspended floor, in an attached Class 10a building or in a roof space, it must –

i. be protected by an outer vapour barrier to prevent the insulation becoming damp and;

ii. the vapour barrier must be sealed with adhesive tape not less than 48mm wide creating an airtight and waterproof seal.

Table 4.22 Heating and Cooling Ductowrk and Fittings - Minimum material R-value

Ductwork element Minimum material R- value for ductwork and fittings in each Climate Zone

Heating only system or cooling only system incl. an evaporative cooling system

Combined heating and refrigerated cooling system

1,2,3,4,5,6 & 7 8 1,3, 4, 6 & 7 2 & 5 8Ductwork 1.0 1.5 1.5 (see Note) 1.0 1.5Fittings 0.4 0.4 0.4 0.4


Note: The minimum material R-Value required for ductwork may be reduced by 0.5 for combined heating and refrigerated cooling systems in climate zones 1, 3, 4, 6, and 7 if the ducts are—

a) under a suspended floor with an enclosed perimeter; or b) in a roof space that has insulation of not less than R0.5 directly beneath the roofing


TIP: 1. Water heating accounts for 25 per cent of the energy used in an average home and is

responsible for 23 per cent of the total greenhouse gas emissions from home energy use. Reducing your hot water use and using renewable energy sources to heat water are great ways to reduce your environmental impact.

2. About 30 per cent of the energy used to heat water in a storage system is wasted due to heat loss from the tank and associated pipework. This can be reduced through careful design and installation.

(REF: Your Home Technical Manual)


Heated water servicesTable 4.23 Application of 3.12.5.6 - Hot Water Supply

State/Territory 3.12.5.6 Water Heater in a hot water supply systemACT AppliesNSW AppliesNT AppliesQLD AppliesSA 3.12.5.6 (a,b &D) is replaced in SA – see State/Territory

Appendix 8TAS AppliesVIC AppliesWA Applies

For each new Class 1a building, or alterations and/or additions to a Class 1a building involving increasing the heated water service a water heater in a hot water supply system must be—

i. a solar heater or a heat pump heater must have the following performance:i. For a building with 1 or 2 bedrooms— at least 14 Renewable Energy Certificates8 for the

zone where it is being installed or an energy saving of not less than 40% in accordance with AS/NZS 4234 (small load).

ii. For a building with 3 or 4 bedrooms - at least 22 for the zone where it is being installed or an energy saving of not less than 60% in accordance with AS/NZS 4234 (medium load).

iii. For a building with more than 4 bedrooms— at least 28 Renewable Energy Certificates for the zone where it is being installed an energy saving of not less than 60% in accordance with AS/NZS 4234 (large load).

(b) a gas water heater rated at not less than 5 stars in accordance with AS 4552 Gas fired water heaters for hot water supply and/or central heating

(c) an electric resistance heater only in the circumstances described in the NCC.

NOTE: Energy ratings are provided for each model of gas water heater in the Australian Gas Association Directory of certified gas appliances and components

8 Renewable Energy Certificate means a certificate issued under the Commonwealth Government’s Mandatory Renewable Energy Target Scheme.


TIP:

Water heating accounts for 25% of a households energy use. Efficient hot water systems save energy, water and money.

(REF: Your Home Technical Manual)


4.4 Low-rise construction: Lighting

Natural LightingNatural lighting must be provided to all habitable rooms of a Class 1A building. Whilst this is a NCC requirement it also adds to the quality of the indoor environment and can reduce the need for electric lighting.

Methods and extent of natural lightingIn a Class 1a building natural lighting to habitable rooms must be provided by windows that:

a) have an aggregate light transmitting area measured exclusive of framing members, glazing bars or other obstructions of not less than 10 percent of the floor area of the room;

b) are open to the sky or face a court or other space open to the sky or an open verandah, carport or the like and roof lights that—

a) have an aggregate light transmitting area measured exclusive of framing members, glazing bars or other obstructions of not less than 3% of the floor area of the room; and

b) are open to the sky;

or a proportional combination of windows and roof lights.

A window required to provide natural light that faces a boundary of an adjoining allotment must not be less than a horizontal distance of 900 mm from that boundary

Natural light borrowed from an adjoining roomNatural lighting to a room in a Class 1a building may come through a glazed panel or opening from an adjoining room (including an enclosed verandah) if:

a) the glazed panel or opening has an area of not less than 10 percent of the floor area of the room to which it provides light; and

b) the adjoining room has windows, excluding roof lights that have an aggregate light transmitting area of not less than 10% of the combined floor area of both rooms; and are open to the sky or face a court or other space open to the sky or an open verandah, carport or the like; or

c) roof lights that have an aggregate light transmitting area of not less than 3% of the combined floor area of both rooms; and are open to the sky; or

d) a proportional combination of windows and roof lights


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Figure 4.23 Method of Determining Areas of Openings for Borrowed Light

Artificial lightingArtificial lighting must be provided to a sanitary compartment, bathroom, shower room, airlock or laundry in a Class 1a building if natural lighting of a standard equivalent to that required to habitable rooms is not available.

This must be achieved by the provision of artificial lighting either:

(a) at a rate of not less than one light fitting per 16m² of floor area; or

(b) in accordance with AS 1680.

See Appendix C for details of Maximum illumination power density.

4.5 Low-rise construction: Natural ventilationVentilation must be provided to a habitable room, sanitary compartment, bathroom, shower room, laundry and any other room occupied by a person for any purpose by having permanent openings,


Note:

Illumination power density means the total of the power (in W/m2) that will be consumed by the lights in a space, including any lamps, ballasts, current regulators and control devices other than those that are plugged into socket outlets for intermittent use such as floor standing lamps, desk lamps or work station lamps, divided by the area of the space.


windows, doors or other devices which can be opened with an aggregate opening or openable size not less than 5% of the floor area of the room required to be ventilated.

They must open to a suitably sized court, space open to the sky, open verandah, carport etc or an adjoining room if the room to be ventilated or the adjoining room is not a sanitary compartment.

This room must also have the window, opening, door or other device has a ventilating area of not less than 5% of the floor area of the room to be ventilated.

An exhaust fan or other means of mechanical ventilation may be used to ventilate a sanitary compartment, laundry or bathroom provided contaminated air exhausts directly to outside the building by way of ducts into a roof space that is adequately ventilated.

Figure 4.24 Method of determining areas of opening for borrowed ventilation

Restriction on position of sanitary compartmentsA sanitary compartment must not open directly into a kitchen or pantry unless access is by an airlock, hallway or other room or mechanical exhaust ventilation is provided.

Figure 4.25 Acceptable location of non-mechanically ventilated sanitary compartment



4.6 Low-rise construction: Sound insulationAirborne sound is measured by the weighted sound reduction index with spectrum adaptation term (Rw + Ctr). Rw is a measure of the sound insulation performance of a building element as measured in a laboratory. Ctr is a value used to adjust the measured sound insulation for low frequency bass noise (from modern sound systems).

The determination of Rw + Ctr must be in accordance with AS/NZS 1276.1 or ISO 717.1 using results from laboratory measurements.

Table 4.24 Sound Insulation – State territoryState/Territory 3.8.6– Sound Insulation – State Territory Appendix 6 (NCC)

ACT AppliesNSW AppliesNT Replaced with NT Acceptable construction practice – See NT

Appendix 6QLD AppliesSA AppliesTAS AppliesVIC AppliesWA Applies

Table 4.25 Required Rw Airborne and Impact Sound Levels for Separating Walls

Separating wall – location and penetrationsDiscontinuous construction required

Rw + Ctr (as per Table 4.26Table 4.5)

Between a bathroom, sanitary compartment, laundry or kitchen and a habitable room (other than a kitchen) in an adjoining Class 1 building (see Figure 3.8.6.1)

Yes 50

In all other cases to those listed above. (See Figure 3.8.6.1) No 50Duct, Soil, Waste, and Water Supply Pipes and Stormwater PipesA duct, soil, waste or water supply pipe or storm water pipe that passé through a separating wall between Class 1 buildings-

a) if the adjacent room is a habitable room (other than a kitchen)b) if the room is a kitchen or any other room. No 40

No 25(NCC Table 3.8.6.1)

Note: Discontinuous construction means a wall system having a minimum 20 mm cavity between two separate leaves,

a) for masonry, where wall tiles are required to connect leaves, the tiles are of the resilient type, and

b) for other masonry, there is no mechanical linkage between leaves except at the periphery.

A staggered stud wall is not deemed discontinuous construction.



For Class 1a dwellings compliance with the impact sound requirements is achieved by using discontinuous construction.

Figure 4.26 Required airborne and impact sounds insulation - plan view

(NCC Figure 3.8.6.1)



4.7 General installation requirements for wallsTo achieve the appropriate level of sound insulation, walls must be constructed as outlined below and the junction with any perimeter walls and roof cladding sealed in accordance with Figure 4.27.

Figure 4.27 sound insulation between buildings - staggered stud wall configuration


Masonry units must be laid with all joints filled solid, except for adequately sound insulated articulation joints, including those between the masonry and any adjoining construction.

Concrete panels must have joints between panels and any adjoining construction filled solid.

Plasterboard must be installed with the joints staggered on opposite sides If two layers are required, the second layer joints must not coincide with those of the first layer (See Figure 4.28). Outer layer and joints between sheets must be taped and filled solid.

Figure 4.28 Typical installation of plaster sheets for sound insulation




Steel framing and perimeter members must be installed as follows:

i. The section of steel must be not less than 0.6 mm thick.ii. Studs must be not less than 63 mm in depth unless another depth is specified in Table 4.26

(NCC table 3.8.6.2)iii. Studs must be fixed to steel top and bottom plates of sufficient depth to permit secure fixing of

the plasterboard.iv. All steel members at the perimeter of the wall must be securely fixed to the adjoining structure

and bedded in resilient compound or the joints must be caulked so that there are no voids between the steel members and the wall.

Timber studs and perimeter members must be installed as follows:

i. Studs must be fixed to top and bottom plates of sufficient depth to permit secure fixing of the plasterboard.

ii. Noggings and like members must not bridge between studs supporting different wall leaves.

iii. All timber members at the perimeter of the wall must be securely fixed to the adjoining structure and bedded in resilient compound or the joints must be caulked so there are no voids between the timber members and the wall.

Table 4.26 Acceptable forms of construction




Description Rw+Ctr

(not less than)

Construction

Wall construction type: MasonryTwo leaves of 110mm clay brick masonry witha) cavity not less than 50 mm between

leaves; and 50

b) 50 mm thick glass wool insulation with a density of 11 kg/m3 or 50 mm thick polyester insulation with a density of 20 kg/m3 in the cavity

Two leaves of 110mm clay brick masonry with: a) cavity not less than 50 mm between

leaves; and50b) 13mm cement render on each outside

face. Single leaf of 110mm clay brick masonrya) a row of 70 mm x 35 mm timber studs or

64 mm steel studs at 600 mm centres, spaced 20 mm from the masonry wall; and 50

b) 50 mm thick mineral insulation or glass wool insulation with a density of 11 kg/m3 positioned between studs; and

c) one layer of 13 mm plasterboard fixed to outside face of studs and outside face of masonry.

Single leaf of 90 mm clay brick masonry with:a) a row of 70 mm x 35 mm timber studs or

64 mm steels studs at 600 mm centres, spaced 20 mm from each face of the masonry wall; and

50

b) 50 mm thick mineral insulation or glass wool insulation with a density of 11 kg/m3 positioned between studs in each row; and

c) one layer of 13 mm plasterboard fixed to studs on each outside face

Single leaf of 220mm brick masonry with 13mm cement render on each face

50

Wall construction type: concrete150 mm thick plain off form concrete 50

200 mm thick concrete panel with one layer of 13 mm plasterboard or 13 mm cement render on each face

50

100mm thick concrete panel witha) a row of 64 mm steel studs at 600 mm

centres, spaced 25 mm from the concrete panel; and

50

b) 80 mm thick polyester insulation or 50 mm thick glass wool insulation with a density of 11 kg/m3, positioned between studs; and

c) two layers of 13 mm plasterboard fixed to outside face of studs and one layer of 13 mm plasterboard fixed to outside face of concrete panel

125mm thick concrete panel witha) a row of 64 mm steel studs at 600 mm

centres, spaced 20 mm from the concrete 50


(NCC Table 3.8.6.2)

ServicesServices must not be chased into concrete or masonry separating walls. If a duct, soil, waste, water supply or storm water pipe serves or passes through a separating wall or is located in a separating wall, special construction is required for any a door or panel used to provide access to a duct or pipe.

In the case of a water supply pipe, it must only be installed in discontinuous construction; and in the case of a water supply pipe that serves one dwelling, not be fixed to the wall leaf on the side of any other dwelling and have a clearance not less than 10 mm to the other wall leaf.

Electrical outlets must be offset from each other in masonry walling, not less than 100 mm; and in timber or steel framed walling, not less than 300 mm.

4.8 ConclusionThis chapter has introduced you to some of the detail from the National Construction Code that needs to be applied during construction, and addresses the energy efficiency requirements that affect a dwellings performance. Building more sustainable structures starts with design but does not achieve the intended purpose without following the NCC. The rules relating to energy efficiency, lighting and ventilation ensure that a dwelling has an improved performance and contributes to reducing environmental impacts and reduced energy bills.



5 Apply Fire Protection RequirementsThis is the last chapter in the Energy Efficiency and the Law unit. The previous chapters have provided an introduction to climate change and the role of the National Construction Code in shaping a response to the need for more sustainable buildings. This chapter covers off fire protection which is extremely important for the safe occupation of our buildings. Now that you are familiar with sustainability in design and construction you need to be aware of how this might affect the insulation of building materials such as insulation and lights.

5.1 National Construction Code (NCC)The National Construction Code (NCC) sets the requirements for the fire safety requirements of buildings. For Class 1 dwellings and Class 10 buildings BCA Volume 2 has the performance requirements and the Deemed to Satisfy requirements.

State and territory rules and regulations also have deemed to satisfy fire safety provisions and small variations to the NCC in certain areas. The NCC Fire safety provisions cover fire separation, smoke alarms, heating appliances, bushfire areas and alpine areas.

5.2 Passive Fire Control Elements for Low-risePassive fire safety is the protection of a building from fire through:Compartmentation9 is the division of a large building into smaller more manageable areas

(with respect to fire safety and smoke control)envelope protection is the fire protection of the external elements of the buildingstructural fire protection is the fire protection of the structural elements.

Fire separation performance requirementThe NCC performance requirement states that—

(a) A Class 1 building must be protected from the spread of fire from –

Another building other than an associated Class 10 building, and

The allotment boundary, other than a boundary adjoining a road or public space (see Figure 5.29) the function and use of the building; and

(b) A Class 10a building must not significantly increase the risk of the spread between Class2 to 9 buildings.

9 Compartmentation requires building construction to be of a specified structural adequacy, integrity and insulation for a specified period of time and includes walls, floors, ceilings and doors.


TIP

The fire safety benefits derived from compartmentation also offer the ability to improve energy efficiency by only heating and cooling as much of a dwelling as is being occupied.


Figure 5.29 Typical Areas of Potential Fire Spread

Note: Figure 5.29 indicates areas of potential fire spread. The situation will differ for corner allotments etc.

Definitions related to fire protectionDwelling: A building or part of a building used as a Class 1 self-contained residence.

External Wall: An outer wall of a building that is not a common wall.

Common Wall: A wall that is common to adjoining buildings (e.g. a terrace house)

External wallsAn external wall of a Class 1a building, and any openings in that wall, must be fire resisting if the wall is less than-

900mm from an allotment boundary (measured at right angles from any given point along the allotment boundary) other than the boundary adjoining a road alignment or other public space

1.8m from another building on the same allotment (measured at right angles from any given point along the wall face of the other building) other than an appurtenant Class 10 building or a detached part of the same Class 1 building.

Where an external wall is required by (a) to be fire resisting, only that part of the wall (including openings) within the specified distance and facing or parallel to the boundary or building on the same allotment need be fire resisting. Walls at right angles or more to the boundary are not required to be fire resisting (refer )



Figure 5.30 Walls at Right Angles to the Boundary

Notes:

(a) No protection required for the wall at right angles or more to the boundary(b) For protection of encroachments refer to Table 5.27

Materials that meet non-combustible housing provisionsThe following materials, though combustible or containing combustible fibres, may be used wherever a non-combustible material is required in the Housing Provisions -

(a) plasterboard

(b) perforated gypsum lath with a normal paper finish

(c) fibrous-plaster sheet

(d) fibre-reinforced cement sheeting

(e) pre-finished metal sheeting having a combustible surface finish not exceeding 1 mm thick and where the Spread-of-Flame Index of the product is not more than 0

(f) bonded laminated materials where—

(i) each laminate is non-combustible

(ii) each adhesive layer is not more than 1 mm thick

(iii) the total thickness of adhesive layers is not more than 2 mm

(iv) the Spread-of-Flame Index and the Smoke-Developed Index of the laminated material as a whole does not exceed 0 and 3 respectively

Construction of external wallsExternal walls (including gables) required to be fire-resisting must extend to the underside of a non-combustible roof covering or non-combustible eaves lining (See Figure 5.31) and must either -

(i) have a Fire Resistance Level (FRL) of not less than 60/60/60 when tested from the outside



(ii) be of masonry-veneer construction in which the external masonry veneer is not less than 90 mm thick

(iii) be of masonry construction not less than 90 mm thick.

Openings in external walls required to be fire-resisting must be protected by either-

(i) non-openable fire windows or other construction with an FRL of not less than -/60/-

(ii) self-closing solid core doors not less than 35 mm thick.

Sub-floor vents, roof vents, weepholes, control joints, construction joints and penetrations for pipes, conduits and the like need not be protected.

There are concessions for non-habitable room windows.

Despite the requirements above, in a non-habitable room, a window that faces the boundary of an adjoining allotment may be not less than 600 mm from that boundary or, where the window faces another building on the same allotment, not less than 1200 mm from that building provided that—

(i) in a bathroom, laundry or toilet, the opening has an area of not more than 1.2 m2; or

(ii) in a room other than referred to in (i), the opening has an area of not more than 0.54 m2 and—

(a) the window is steel-framed, there are no opening sashes and it is glazed in wired glass; or

(b) the opening is enclosed with translucent hollow glass blocks

Figure 5.31 Typical Construction of External Walls


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Notes:1. The external wall is deemed to extend to the underside of non-combustible roof covering, or non-

combustible eaves lining, when constructed as shown. 2. Where sarking is installed it must be located so that ponding of water is avoided between the fascia

and the first roofing batten.3. The location of flashing and framing is indicative only.

Class 10a buildingsWhere a Class 10a building is located between a Class 1 building and the allotment boundary, other than the boundary adjoining a road alignment or other public space, the Class 1 building must be protected by one of the following methods shown in Table 5.27

Where a Class 10a building is located between a Class 1 building to which it is appurtenant and another building on the same allotment, the Class 1 building must be protected by one of the methods shown in Table 5.28.

Where two or more Class 10a buildings on the same allotment are appurtenant to different Class 1 buildings, the Class 10a buildings must be separated in accordance with one of the methods shown in Table 5.29.



Table 5.27 Protection of Class 1 buildings10

Legend:Wall with an FRL of 60/60/60 Allotment boundary

a 900mm from an allotment boundaryThe Class 10a building is not less than 900 mm from the allotment boundary, other than the boundary adjoining a road alignment or other public space

b External wall to Class 10a building with FRLAn external wall of the Class 10a building which is less than 900 mm from an allotment boundary, other than the boundary adjoining a road alignment or other public space, complies

c External wall to Class 10a building with FRLAn external wall of the Class 10a building which is less than 900 mm from the Class 1 building complies

d 900mm separation between buildings

e Class 1 building with FRL to external wallAn external wall of the Class 1 building which is less than 900 mm from the Class 10a building complies

10 Class 10a between Class 1 and the allotment boundary



Table 5.28 Protection of Class 1 buildings11

Legend:Wall with an FRL of 60/60/60 Other Class building on allotment

a 1.8m from other buildings on allotmentThe Class 10a building is not less than 1.8 m from the other building

b External wall to Class 10a building with FRLAn external wall of the Class 10a building which is less than 1.8 m from the other building complies

c External wall to Class 10a buildings with FRL An external wall of the Class 10a building which is less than 1.8 m from the Class 1 building complies

d 1.8m separation between Class 1 and 10a buildingsThe Class 1 building is not less than 1.8 m from the Class 10a building.

e Class 1 building with FRL to external wallAn external wall of the Class 1 building which is less than 1.8 m from the Class 10a building complies.

11 Class 10a between Class 1 and other buildings on allotment



Table 5.29 Protection of Class 1 buildings - separation of Class 10a buildings on an allotmentLegend:

Wall with an FRL of 60/60/60

a 1.8m between Class 10a buildings boundaryEach 10a building must be separated from each other by a distance of not less than 1.8m

b External wall to Class 10a building with FRLEach 10a building must be separated from each other by external walls complying

c 900mm separation between Class10a and Class 1 buildings

Each 10a must be separated from each Class 1 building by a distance of not less than 900 mm

d External wall to Class 10a buildings with FRLEach 10a building must be separated from each Class 1 building by external walls complying.

e Class 10a buildings with FRL to separating wallEach 10a must be separated by a wall complying with required FRL etc.

CarportsA carport is exempt if:-

i. it has two or more sides open and not less than one third of its perimeter open and, for the purposes of this clause, a side is considered to be open if the roof covering adjacent to that side is not less than 500 mm from another building or allotment boundary

ii. it has a polycarbonate or non-combustible roof covering and any ceiling lining and wall cladding, including gables, is also non-combustible (see Table 5.29).

iii. it does not provide direct vertical support to any part of the Class 1 building

iv. in the case where it has a common roof structure with the Class 1 building and the carport does not have a ceiling (see Figure 5.33), the opening between the top of the wall of the Class 1 building and the underside of the roof covering is in filled with:



a. a non-combustible material; or

b. construction clad with non-combustible material on the carport side.

Figure 5.32 Identifying an Open Carport



Figure 5.33 Requirements for non-combustible infill panels to carport

Class 10a buildings must not significantly increase the risk of spread of fire between Class 2 to 9 buildings.

Allowable encroachmentsAn encroachment is any construction between the external wall of the building and the allotment boundary other than a boundary adjoining a road or other public space, or the external walls of two buildings on the same allotment and relates to any external wall of -

(i) a Class 10a building required to comply with fire protection requirements

(ii) a Class 1 building.

The encroachments allowed within 900 mm of an allotment boundary or within 1.8 m of another building on the same allotment are:

(i) fascias, gutters and downpipes(ii) eaves with non-combustible roof cladding and non-combustible lining(iii) flues, chimneys, pipes, domestic fuel tanks, cooling or heating appliances or other

services(iv) light fittings, electricity or gas meters, aerials or antennas(v) pergolas, sun blinds or water tanks(vi) unroofed terraces, landings, steps and ramps, not more than 1 m in height.



Encroachments listed in above must not be built within 450 mm of an allotment boundary nor be built within 900 mm of the external wall or associated encroachments of another building on the same allotment. (see Figure 5.34).

Figure 5.34 Allowable encroachment for non-combustible construction

Separating wallsA separating wall between Class 1 buildings, or a wall that separates a Class 1 building from a Class 10a building which is not appurtenant to that Class 1 building must have an FRL of not less than 60/60/60 and -

(i) commence at the footings or ground slab(ii) extend—

(a) if the building has a non-combustible roof covering, to the underside of the roof covering

(b) if the building has a combustible roof covering, to not less than 450 mm above the roof covering

A separating wall of lightweight construction must be tested in accordance with Specification C1.8 of the NCC Volume One.

Figure 5.35 Separating wall construction



A separating wall that has a non-combustible roof covering-

i. must not be crossed by timber or other combustible building elements except for roof battens with dimensions of 75x50 mm or less, or roof sarking

ii. must have any gap between the top of the wall and the underside of the roof covering packed with mineral fibre or other suitable fire-resisting material.

Where a building has a masonry veneer external wall, any gap between the separating wall and the external masonry veneer must be—

i. not more than 50 mm

ii. packed with a mineral fibre or other suitable fire resistant material with the packing arranged to maintain any weatherproofing requirements.

Eaves, verandahs and similar spaces that are open to the roof space and are common to more than one Class 1 dwelling must be separated by a non-combustible vertical lining.

Any service opening in a separating wall must have construction with an FRL of not less than -/60/60

Figure 5.36 Separating wall construction - underside of non-combustible roof claddingDiagram a.

Diagram b.



Diagram c.

Roof lightsCombustible roof lights, skylights or the like installed in a roof or part of a roof required to have a non-combustible covering must—

i. have an aggregate area not more than 20% of the roof or part of the roof; and

ii. be not less than—

a. 900 mm from—

A. the allotment boundary other than the boundary adjoining a road alignment or other public space; and

B. the vertical projection of a separating wall extending to the underside of the roof covering; and

b. 1.8 m from any roof light or the like in another building on the allotment other than an appurtenant building or a detached part of the same building. (See Figure 5.37)

Figure 5.37 Location of combustible roof lights

Note: the roof lights depicted in Figure 5.37 are combustible.



5.3 Active fire control elements for low riseActive fire protection is the use of controlled methods to extinguish or control the spread of a fire and the products of fire and smoke.

Active fire control elements include:

smoke alarmsfire blanketsfire extinguishersfire hose reelshydrants fire booster pointsthermal alarmssmoke extractionair pressurisation

Smoke alarmsP2.3.2 Fire detection and early warningIn a Class 1 building, occupants must be provided with automatic warning on the detection of smoke so that they may evacuate in the event of a fire to a place of safety.

GeneralSelf-contained smoke alarms shall comply with AS 3786 or be listed in the SSL Register of Accredited Products and shall be connected to the consumer mains power unless the building is not connected to the consumer mains power. There is no requirement for smoke alarms to be on a separate circuit.

InstallationSelf-contained smoke alarms must be installed in Class 1a building on or near the ceiling in:

i. any storey containing bedrooms:

a. between each part of the dwelling containing bedrooms and the remainder of the dwelling; and

b. where bedrooms are served by a hallway, in that hallway; and

ii. any other storey not containing bedrooms.

Figure 5.38 Location of smoke alarms


TIP

The use of roof lights can assist with energy efficiency in many homes. Correct positioning and satisfying fire regulations is essential.


Legend:Smoke alarm Smoke alarm with evacuation lighting (as required by NCC 3.7.2.5(b)

(i))

a Class 1a buildings

b Class 1b buildings

Figure 5.39 Location of smoke alarms on different storeys

Note: smoke alarms installed on each storey not containing bedrooms – located in the area of the stairway.



Types of smoke alarmsThere are two types of smoke alarms.

Photoelectric: This type of smoke alarm uses a light source and photocell. As the smoke enters the detection chamber it interferes with the light beam which in turn causes the alarm to sound.

Ionisation: A small amount of radioactive material is used to create an electrical current which travels through ionised air. When smoke enters the detection chamber it impedes the flow of current and causes the alarm to sound.

Location of smoke alarmsWhen deciding on the position of smoke alarms it is important to remember that they are intended to detect smoke before it reaches the sleeping occupants of a building. The ensuing alarm is designed to wake the occupants and give them time to evacuate the building.

Added flexibility when considering detector locationAs mentioned earlier, the introduction of the Performance Requirement gives the appropriate authority flexibility when considering the location of smoke alarms.

For example, in Class 1a buildings if the Deemed-to-Satisfy Provision states that the smoke alarm should be located in the hallway, and there is a bathroom adjacent this location (that will potentially cause nuisance alarms) the appropriate authority could accept the alarm being installed in the bedroom as a suitable option using the performance clause.

This approach should also be adopted when considering sleep-outs or similar type residential buildings that are not connected to the remainder of the building by a hallway or other enclosed structure. In these situations the alarm could be located in the room itself.

Location of the smoke alarm on other storiesA smoke alarm is also required on each other storey that is not already provided with a smoke alarm. It should be noted that smoke alarms are required to be installed in other stories even if those stories consist of only carparking, bathrooms, laundries and the like. “Storey” in this context differs from the definition contained in NCC Volume One which excludes such spaces from being considered as stories.

The favoured location for this alarm will be in the path of travel people will most likely take to evacuate the building. This will ensure an alarm will be raised before smoke makes the common exit path impassable. e.g. If the bedrooms are on the first floor, then an alarm should be positioned near the area of the inter-connecting stair at ground level.

If the other storey is not connected to the remainder of the building (for instance a ground floor garage) then the alarm should be centrally located in the lower area.

However, it may be reasonable, using a performance approach, not to install smoke alarms where the storey is predominantly open, such as the basement level of a highset house on stumps that is used for carparking or laundry purposes

Figure 5.40 Dead airspace and proper mounting of smoke alarms on side walls



Installation of smoke alarmsSmoke alarms should be installed on or near the ceiling with special care being taken to avoid dead air spaces.

A dead air space is an area in which trapped hot air will prevent smoke from reaching the alarm. This space generally occurs at the apex of cathedral ceilings, the corner junction of walls and ceilings, between exposed floor joists etc.

If it is impractical to mount the smoke alarm on the ceiling then it may be located on the wall. The recommended position is between 300 mm and 500 mm off the ceiling.

The distance from the apex of a cathedral ceiling to the top of the alarm should be between 500 mm and 1500 mm.

Nuisance alarmsSmoke alarms are extremely sensitive and may detect smoke and moisture created by common household activities (such as burnt toast or steam from a bathroom).

Accordingly, to reduce the likelihood of nuisance alarms, the smoke alarm should not be located near cooking appliances and bathrooms. However, if it is necessary to locate alarms in these positions, an ionisation type alarm is more suitable near bathrooms, while a photoelectric alarm may be used near cooking appliances.

Interconnection of smoke alarmsSome types of alarm are capable of interconnection to the other alarms so that if one alarm sounds then the other alarms are also activated adding an enhanced level of safety. There is no requirement in the NCC that smoke alarms be interconnected.



5.4 Fire resistance for low-rise buildings

P2.3.3 Heating appliancesA heating appliance and its associated components within a building, including an open fire-place, chimney, or the like, must be installed—

i. to withstand the temperatures likely to be generated by the appliance; and

ii. so that it does not raise the temperature of any building element to a level that would adversely affect the element’s physical or mechanical properties or function; and

iii. so that hot products of combustion will not—

a. escape through the walls of the associated components; and

b. discharge in a position that will cause fire to spread to nearby combustible materials or allow smoke to penetrate through nearby windows, ventilation inlets, or the like in the building containing the heating appliance.

Open fireplace constructionAn open fireplace must be constructed as follows:

All masonry must be constructed in accordance with the NCC.

i. The front hearth must be constructed of stone, concrete, masonry or similar material so that it extends not less than 300 mm beyond the front of the fireplace opening and not less than 150 mm beyond each side of that opening; and its upper surface does not slope away from the back hearth.

ii. The base of the back hearth must be constructed of stone, concrete, masonry or similar material and any combustible flooring or framing members must be situated not less than 150 mm from its upper surface.

iii. The fireplace rear and side walls up to a height of 300 mm above the underside of the arch or lintel— (a) must be constructed in 2 separate leaves of solid masonry with an overall thickness not

less than 180 mm thick, excluding any cavity; and

(b) must not consist of concrete block masonry in the construction of the inner leaf; and

(c) must be constructed of masonry units with a net volume, excluding cored and similar holes, not less than 75% of their gross volume, measured on the overall rectangular shape of the units, and with an actual thickness of not less than 100 mm.

The fireplace must be constructed on footings complying with the NCC.

Figure 5.41 Fire place clearance from combustible materials



Chimney constructionThe construction of a chimney must comply with the NCC and the following:

i. The walls of the chimney above the level must be lined internally to a thickness of not less than 10 mm with composition mortar parging12.

12 Parging is a construction technique used to finish the surface of a masonry wall. It is similar to stucco, but uses a masonry-based mortar rather than a traditional stucco mixture


DESIGN TIP

When installing heating appliances it is important to also consider the overall design of the building so that heat generated is used efficiently. This might be by installing doors to prevent heat loss to other areas of the building.


ii. The chimney or flue must terminate not less than 300 mm above the highest part of the building within a horizontal distance of 3.6 m of the chimney or flue

Figure 5.42 Section showing height and position of chimney

Bushfire areas requirementsPerformance Requirement P2.3.4 is satisfied for—

i. a Class 1 building; orii. a Class 10a building or deck associated with a Class 1 building, located in a designated bushfire prone

area if it is constructed in accordance with AS3959 - Construction of buildings in bushfire prone areas13.

A Class 1 building or a Class 10a building or deck associated with a Class 1 building that is constructed in a designated bushfire prone area must be designed and constructed to reduce the risk of ignition from a bushfire while the fire front passes.

Alpine areasi. An external doorway from a building in an alpine area must be installed so that opening the

door is not obstructed by snow or ice.

13 Designated bushfire prone area means land which has been designated under a power in legislation as being subject, or likely to be subject, to bushfires.



ii. A building in an alpine area containing external trafficable structures forming part of the means of egress must be constructed so that they remain, as far as practicable, useable under snow conditions.

iii. A building in an alpine area must be constructed so that snow or ice is not shed from the building onto the allotment, any adjoining allotment, road or public space in a location or manner that will—

a. obstruct a means of egress from any building to a road or open space; or

b. otherwise endanger people

Table 5.30 NCC Bushfire area rules appliedState/Territory 3.7.4 Bushfire Areas – NCC

ACT AppliesNSW Is replaced in NSW with a specific clauseNT AppliesQLD AppliesSA Is replaced in SA with a specific acceptable construction practiceTAS Is replaced in Tasmania with a specific clauseVIC AppliesWA Applies

5.5 ConclusionBy completing this chapter you will be familiar with the rules regarding fire protection of the dwellings that you construct. It is important that you maintain a thorough understanding of fire protection and use this knowledge during both the design and construction phases of projects you are involved in.

The way in which occupants use a dwelling can affect the sustainability performance of it. At all times fire protection requirements must be adhered to. In some areas, compartmentation for fire purposes matches design for sustainability by heating and cooling smaller areas of the dwelling.

The National Construction Code is a comprehensive framework that guides construction for safe occupation of dwellings. The NCC adds to the ongoing suitability and sustainability of dwellings in Australia.


Class 2 ApartmentsClass 2 ApartmentsClass 2 ApartmentsClass 2 Apartments

Class 6 Shops on Ground levelClass 7 Car parkClass 7 Car park

Appendix A Difficult ClassificationsClass 2 or Class 3?There is a fine line between a Class 2 building and a Class 3 building with a bathroom and cooking equipment in its units.

For example, when does a motel unit (probably Class 3) become a holiday flat (probably Class 2) and vice versa?

In general, an assessment will be based on the most likely use of the building by appropriate authorities. Class 3 buildings represent a higher risk level, and therefore require higher safety levels. In a case where the classification is unclear, perceived risks inherent in the use of the building will be scrutinised.

Traditionally, there have been difficulties in assessing the use of class 2 or 3 buildings. A certain degree of clear thinking has been necessary and this process is usually assisted by requiring a “statement of use” and an explanation of the operation and management of a facility. Discrepancies do occur in the description of the use of a building and our experience indicates this can occur because of the terminology differences between planning schemes and the NCC.

Another concern arises when a class 2 or 3 use is constructed above another commercial use which does not require any smoke hazard management provision whereas the class 2 or 3 part does. That is to say the class 2 or 3 use is compromised because the commercial use is below the level of requiring any smoke hazard management provision, other than when they share the same fire stair

Farm BuildingsIn some States or Territories, appropriate authorities may classify farm buildings as Class 10a, which covers non-habitable buildings. They would only make this decision if a classification of Class 7 or Class 8 would not be more appropriate. When making their decision they consider the building's size, purpose, operations and the extent to which people are employed in the building.

In some states there are specific concessions for farm buildings (eg. South Australia as contained in the Minister's Specification SA H3.2 Concessions and additional requirements for farm buildings

Multiple classificationsWhere there is a multi classification, the ‘most serious’ classification must be selected. If 10% or less of the floor area of a storey is used for a purpose which could be classified differently to the remainder of that storey, that part may be classified as being the same as the remainder. Each part of a building must be classified separately as shown in the diagram opposite.

Laboratories and sole-occupancy units in Class 2, 3 or 4 parts are excluded from this concession. The reason is that laboratories are considered to have a high fire hazard potential and classifying them with


the remainder of the building could, in a majority of cases, endanger occupants of the other part of the building which have a lower fire hazard potential.

Also, the intent is not to allow sole-occupancy units in Class 2, 3 or 4 parts to be regarded as another Class such as Class 6 and then not have any fire or sound insulation between the units and any other classification which may have a high fire load and could endanger the occupants of the Class 2, 3 or 4 part.

If the storey has a very large floor area, the 10% or less concession area may also be large, even though the rest of the building is classifiable as a building which ordinarily has a lower risk potential.

A plant room, machinery room, lift motor room, boiler room or the like must have the same classification as the part of the building in which it is situated.



Appendix B Classification of Buildings and StructuresNCC Class

CLASSIFICATION OF BUILDINGS AND STRUCTURES

1 Buildings are classified as follows: a A single dwelling, being

a detached house; orone of a group of two or more attached dwellings, each being a building, separated by a fire resisting wall, including a row house, terrace house, town house, or villa unit, which is not located above or below another dwelling or another class of building or

b A boarding house, guest house, hostel or the like - with a total area of all floors not exceeding 300m2 measured over the enclosing walls of the Class 1b; andin which not more than 12 persons would ordinarily be resident,which is not located above or below another dwelling or another Class of building other than a private garage.

2 A building containing two or more sole-occupancy units each being a separate dwelling.3 A residential building, other than of Class 1 or 2, which is a common place of long term or transient

living for a number of unrelated persons, includingA boarding house, guest house, hostel lodging house or backpackers accommodationA residential part of a hotel or motelA residential part of a schoolAccommodation for the aged, disabled or childrenA residential part of a healthcare building which accommodates members of staffA residential part of a detention centre.

4 A dwelling in a building that is Class 5, 6, 7, 8 or 9 if it is the only dwelling in the building. 5 An office building used for professional or commercial purposes, excluding buildings of Class 6, 7,

8 or 9.6 A shop or other building for the sale of goods by retail or the supply of services direct to the public,

including:An eating room, café, restaurant, milk or soft drink bar; orA dining room, bar area that is not an assembly building shop or kiosk part of a hotel or motel; orA hairdresser’s or barber’s shop, public laundry or undertakers establishment; orMarket or sale room, show room or service station

7 A building which isa A car park; orb For storage, or display of goods or produce for sale by wholesale

8 A laboratory, or a building in which a handicraft or process for the production, assembling, altering, repairing, packing, finishing, or cleaning of goods or produce is carried out for trade, sale or gain.

9 A building of a public naturea A health-care building, including those parts of the building set aside as a laboratoryb An assembly building including a trade workshop, laboratory or the like in a primary or

secondary school, but excluding any other parts of the building that are of another Class; orc An aged care building.



10 A non-habitable building or structure

a A non-habitable building being a private garage, carport shed or the likeb A structure being a fence, mast, antenna, retaining/ free standing wall, swimming pool or the

like



Appendix C

SpaceMaximum

illumination power density

(W/m2)Auditorium, church and public hall 10Boardroom and conference room 10Carpark - general 6Carpark - entry zone (first 20 m of travel) 25Control room, switch room, and the like 9Corridors 8Courtroom 12Dormitory of a Class 3 building used for sleeping only 6Dormitory of a Class 3 building used for sleeping and study 9Entry lobby from outside the building 15Health-care - children's ward 10Health-care - examination room 10Health-care - patient ward 7Health-care - all patient care areas including corridors where cyanosis lamps are used

13

Kitchen and food preparation area 8Laboratory - artificially lit to an ambient level of 400 lx or more 12Library - stack and shelving area 12Library - reading room and general areas 10Lounge area for communal use in a Class 3 building or Class 9c aged care building

10

Museum and gallery - circulation, cleaning and service lighting 8Office - artificially lit to an ambient level of 200 lx or more 9Office - artificially lit to an ambient level of less than 200 lx 7Plant room 5Restaurant, café, bar, hotel lounge and a space for the serving and consumption of food or drinks

18

Retail space including a museum and gallery whose purpose is the sale of objects

22

School - general purpose learning areas and tutorial rooms 8Sole-occupancy unit of a Class 3 building 5Sole-occupancy unit of a Class 9c aged care building 7Storage with shelving no higher than 75% of the height of the aisle lighting 8Storage with shelving higher than 75% of the height of the aisle lighting 10Service area, cleaner's room and the like 5Toilet, locker room, staff room, rest room and the like 6Wholesale storage and display area 10


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