<Insert Institution Name> Building Code of Australia Training Program MODULE THREE Understanding Energy Efficiency Provisions for Class 1 and 10 Buildings Content of Module 3 • • • • • • • • • Introduction to Module 3 Background to Energy Efficiency Provisions Principles of Energy Efficiency General Scope of Building Code of Australia Provisions Performance Requirements Deemed-to-Satisfy Provisions Alternative Solutions Verification Methods Administrative Matters Introduction to Module 3 Scope of the BCA Methods of Compliance Introduction to Module 3 • This training module is one of a series produced by the Australian Building Codes Board; the organisation responsible for the development and maintenance of the Building Code of Australia (BCA) • For the purposes of this presentation it is assumed that participants have a general understanding of the content of ABCB training Modules 1 and 2 Introduction to Module 3 Scope of the BCA Methods of Compliance Recap on Module 1 • Module 1 was titled; An Introduction to the Building Code of Australia • The object of Module 1 was to provide information on: the background to the development of the BCA the operation of the BCA, and the application of the BCA Introduction to Module 3 Scope of the BCA Methods of Compliance The Building Code of Australia • The BCA establishes minimum standards for new building work • The BCA: is referenced in State /Territory law – see next slide is amended annually requirements are intended to be cost effective is intended to eliminate poor practice does not address best practice Introduction to Module 3 Scope of the BCA Methods of Compliance STATE & TERRITORY BUILDING ACTS STATE & TERRITORY BUILDING REGULATIONS ADMINISTRATIVE MATTERS • Administration • Appeals • Registrations • Refurbishments • Building standard Introduction to Module 3 TECHNICAL STANDARDS Scope of the BCA Methods of Compliance Presentation of the BCA • The BCA is presented in two Volumes • A reason for this is to correlate with the historic operation of the building industry • In general, industry tends to work in either the housing sector or the commercial sector, although some large companies work in both sectors • The BCA endeavours to follow this division Introduction to Module 3 Scope of the BCA Methods of Compliance BCA Volumes One and Two • Volume One contains requirements for the design and construction of commercial buildings; i.e. Class 2 to 9 buildings, plus some Class 10 matters • Volume Two contains requirements for the design and construction of domestic buildings; i.e. Class 1 and 10 buildings, plus some Class 10 structures Introduction to Module 3 Scope of the BCA Methods of Compliance Volumes One and Two Introduction to Module 3 Scope of the BCA Methods of Compliance Recap on Module 2 • Module 2 was titled; Understanding the BCA’s Performance Requirements • The object of Module 2 was to provide information on how to comply with the BCA without using Deemed-toSatisfy Provisions – i.e. by developing an Alternative Solution Introduction to Module 3 Scope of the BCA Methods of Compliance Objective Guidance Functional Statement Performance Requirement Building Solutions DTS Provisions Alternative Solutions Mandatory Methods of achieving compliance Documentary Evidence Verification Methods Comparative Analysis Assessment Methods Expert Judgement Introduction to Module 3 Scope of the BCA Methods of Compliance Objective of Module 3 • The objective of Module 3 is to provide basic information on BCA energy efficiency provisions relating to Class 1, as well as Class 10 buildings with a conditioned space • Information is also available in ABCB publication; Enhanced Energy Efficiency Housing Provisions for BCA 2006 Volume Two • http://www.abcb.gov.au/documents/energy/Handbook_vol2.pdf Introduction to Module 3 Scope of the BCA Methods of Compliance BCA Energy Efficiency • BCA requirements reduce the use of energy from electricity, gas, oil, or other fuels used in buildings for: heating cooling ventilation hot water (heating and sanitary) other domestic services Introduction to Module 3 Scope of the BCA Methods of Compliance BCA Requirements • The BCA only addresses energy used by a building's services to operate • Does not include energy (i.e. embodied energy) used in manufacturing building materials or construction of a building • Does not include portable appliances within a building such as computers or fridges Introduction to Module 3 Scope of the BCA Methods of Compliance Module 3 Background BCA Requirements Alternative Solutions Introduction to Module 3 Scope of the BCA Methods of Compliance Background to BCA Energy Efficiency Provisions General background • Over the past decade international awareness of greenhouse gas (GHG) emissions and their influence on global warming has grown significantly • GHG is a natural part of the Earth’s atmosphere that capture the Sun’s warmth to keep Earth’s surface temperature at a life supporting level Introduction to Module 3 Scope of the BCA Methods of Compliance General background • Increased concentrations of GHG will cause variations to our climate that will differ between geographic regions • Changes may occur to temperatures, rainfall, wind speed, vegetation and animal life • GHG emissions are increasing due to human activities such as land clearing and burning fossil fuel (e.g. coal and oil) Introduction to Module 3 Scope of the BCA Methods of Compliance National background • 1997 - Prime Minister issued a statement on Australia’s response to global warming that included measures to reduce energy consumption in buildings • The building sector was not the largest contributor to national GHG emissions -although it contributed 27% of energy related GHG emissions and was the fastest growing source Introduction to Module 3 Scope of the BCA Methods of Compliance National background • Late 1990’s - governments considered the need for new buildings to operate in an energy efficient manner • It was apparent that market forces had not addressed the issue effectively so there was a need for regulatory reform • Industry generally supported the need to eliminate worst practice in building design Introduction to Module 3 Scope of the BCA Methods of Compliance National background • 2000 – Agreement by the Council of Australian Governments (COAG) to introduce energy efficiency regulations for domestic and commercial buildings • 2001 – In response, the Australian Greenhouse Office (AGO) and the ABCB enter into an agreement to develop energy efficiency provisions and introduce these through the BCA Introduction to Module 3 Scope of the BCA Methods of Compliance National background • 2001- 2002 - Energy efficiency provisions developed for housing • January 2003 - BCA Volume Two introduced 4 star energy efficiency provisions in climate zones 4 to 8 and 3.5 star in climate zones 1 to 3 for housing and associated buildings • Some States/Territories had existing provisions in place and did not adopt new BCA requirements Introduction to Module 3 Scope of the BCA Methods of Compliance National background • BCA 2005 introduced the same stars level energy efficiency requirements for Class 2 and 3 buildings and Class 4 parts • BCA 2006 introduced requirements for Class 5 to 9 buildings, plus enhanced requirements from 3.5 / 4 to 5 star for Class 1 and nominated Class 10a buildings Introduction to Module 3 Scope of the BCA Methods of Compliance What is a star rating? • A star rating is a quantified benchmark used to describe the energy efficiency performance of a building based on a comparative annual energy load • The term is used in one of the BCA Verification Methods and is derived from computer software packages; Firstrate, AccuRate, NatHERS and BERS Introduction to Module 3 Scope of the BCA Methods of Compliance Initial Draft Provisions • Developed through stakeholder committees, specialist working groups and specialist consultants • Proposals were refined through industry and community consultation • Draft provisions subjected to formal Regulation Document process and Regulatory Impact Statement process Introduction to Module 3 Scope of the BCA Methods of Compliance Regulatory Impact Statement • Under 2006 IGA ABCB must only propose new regulation as a final option • All proposals for change to BCA must be subjected to rigorous regulatory impact assessment process that includes cost benefit analysis • A positive cost benefit outcome must be demonstrated Introduction to Module 3 Scope of the BCA Methods of Compliance Environmental and Cost Benefits Energy Efficiency Provisions 2003 Class 1 & 10 buildings 2005 Class 2 to 4 buildings 2006 Class 1 & 10 buildings 2006 Class 5 to 9 buildings Introduction to Module 3 Annual CO2e reduction in 2010 Benefit to cost ratio 380,000 tonne 1.6 : 1 24,000 tonne 1.7 : 1 88,000 tonne 1.3 : 1 1,200,000 tonne 4.6 : 1 Scope of the BCA Methods of Compliance Three Stage Process • Using a three stage process the ABCB has now introduced energy efficiency requirements for all classification of buildings • 2003 - Class 1 & 10 (4 star / 3.5 star) • 2005 - Class 2 to 4 (4 star/ 3.5 star) • 2006 - Class 5 to 9; plus - Class 1 & 10 (5 star) Introduction to Module 3 Scope of the BCA Methods of Compliance Adoption of Provisions Energy Efficiency Provisions WA SA VIC ACT NSW QLD TAS NT 2003 Class 1 & 10 Yes Yes No1 No1 No Yes Yes Yes 2005 Class 2 to 4 Yes Yes Yes Yes Yes2 Yes Yes No 2006 Class 5 to 9 Yes Yes Yes Yes Yes Yes Yes No 2006 Class 1 & 10 Yes Yes Yes Yes No No No No 1 = Existing higher standard 2 = Class 3 buildings only Introduction to Module 3 Scope of the BCA Methods of Compliance Voluntary best practice • The AGO also developed a Voluntary Building Industry Initiatives Program - aimed at assisting designers to go beyond the minimum requirements of the BCA • The Program promotes best practice rather than BCA minimum requirements • Information on this Program can be found at: http://www.greenhouse.gov.au/buildings/practices.html Introduction to Module 3 Scope of the BCA Methods of Compliance Principles of Energy Efficiency Objective of BCA Provisions • The objective of the BCA energy efficiency provisions is to reduce GHG emissions by reducing operational energy use of new buildings without reducing comfort and amenity • BCA requirements primarily address: heat flow - in and out of a building through the building envelope, and domestic services - that use energy e.g. airconditioning and hot water Introduction to Module 3 Scope of the BCA Methods of Compliance Definition of Envelope • Envelope, for the purposes of Part 2.6 and Part 3.12, means the parts of a building’s fabric that separate artificially heated or cooled spaces from – (a) the exterior of the building; or (b) other spaces that are not artificially heated or cooled Introduction to Module 3 Scope of the BCA Methods of Compliance Definition of Domestic Services • Domestic services means the basic engineering systems of a house that use energy or control the use of energy; and (a) includes heating, air-conditioning, mechanical ventilation and hot water systems; but (b) excludes cooking facilities and portable appliances. Introduction to Module 3 Scope of the BCA Methods of Compliance Principles of Energy Efficiency • The efficient performance of the building envelope plus the building's domestic services results in reduced – demand for a service, i.e. in a moderate climate zone, size of a service, operating time of a service, and energy consumption of a service. Introduction to Module 3 Scope of the BCA Methods of Compliance Application of Energy Efficiency requirements • Not all of Australia has the same climate so the BCA DTS provisions applies its requirements across eight (8) climate zones • Climate zone 1 is hot and humid while climate zone 8 is cold • A map of the location of climate zones is provided as Figure 1.1.4 – see next slide Introduction to Module 3 Scope of the BCA Methods of Compliance Climate Zone Map Figure 1.1.4 Introduction to Module 3 Scope of the BCA Methods of Compliance Climate Zone Map • An enlargeable form of the map can be found on the ABCB website at: http://www.abcb.gov.au Introduction to Module 3 Scope of the BCA Methods of Compliance Application of Requirements • The primary intent of the BCA provisions is to reduce energy required for cooling services in warmer climate zones and heating services in cooler climate zones • The extent of specific requirements will generally vary depending on the use of the building and the climate zone in which it is located Introduction to Module 3 Scope of the BCA Methods of Compliance Achieving Energy Efficiency • • • • • Insulating or shading the building fabric Controlling heat flow through glazing Reducing air leakage via building fabric Creating internal air movement for cooling Improving the efficiency of heating, cooling and hot water systems Introduction to Module 3 Scope of the BCA Methods of Compliance General Scope of BCA Provisions Sections of Volume Two • The application of the energy efficiency provisions is governed by the content of Sections 1 and 2 of Volume Two • Section 1 – General Provisions – presents the "general rules" by which the BCA provisions are applied • Section 2 – Performance Requirements – presents the mandatory requirements of the BCA and the Verification Methods Introduction to Module 3 Scope of the BCA Methods of Compliance Sections of Volume Two • Section 3 of Volume Two presents the Deemed-toSatisfy Provisions • These provisions are presented as either an: Acceptable Construction Manual or Acceptable Construction Practice • The principle benefit of using Deemed-to-Satisfy Provisions is that they are accepted as meeting the mandatory Performance Requirements Introduction to Module 3 Scope of the BCA Methods of Compliance Energy Efficiency Performance Requirements Part 2.6 of Volume Two Energy Efficiency Requirements • There are two mandatory Performance Requirements for energy efficiency i.e. P2.6.1 for the thermal performance of buildings P2.6.2 for the energy efficiency of a building's domestic services Introduction to Module 3 Scope of the BCA Methods of Compliance P2.6.1 Building 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 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. Introduction to Module 3 Scope of the BCA Methods of Compliance P2.6.2 Services A building’s domestic services, including any associated distribution system and components must have features that, to the degree necessary, facilitate the efficient use of energy appropriate to – (a) the domestic service and its usage; and (b) the geographic location of the building; and (c) the location of the domestic service; and (d) the energy source Introduction to Module 3 Scope of the BCA Methods of Compliance Domestic Services • Domestic services means the basic engineering systems of a house that use energy or control the use of energy; and (a) includes heating, air-conditioning, mechanical ventilation and hot water systems; but (b) excludes cooking facilities and portable appliances Introduction to Module 3 Scope of the BCA Methods of Compliance Energy Efficiency Deemed-to-Satisfy Provisions Part 3.12 of Volume Two Section 3 - Part 3.12 • Section 3 of Volume Two presents optional Deemedto-Satisfy Provisions that may be used to achieve compliance with the mandatory Performance Requirements • Part 3.12 presents the optional Deemed-to-Satisfy Provisions for the energy efficiency Performance Requirements Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12 – Energy Efficiency • The Deemed-to-Satisfy Provisions address the following parts of a building; 3.12.1 Building Fabric 3.12.2 External Glazing 3.12.3 Building Sealing 3.12.4 Air Movement 3.12.5 Services Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.1 - Building Fabric • Provisions for Building fabric address: Thermal insulation Roofs Roof lights External walls Floors Attached Class 10a buildings Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.1 - Building Fabric • The intent of these provisions is to ensure the building envelope is an effective means of resisting heat flow • Heat flow may be either into or out of a building – depending on the climate zone • A thermally efficient building envelope means less energy is needed to artificially heat or cool internal spaces Introduction to Module 3 Scope of the BCA Methods of Compliance Performance of a typical envelope Proportion of envelope heat gain roof floor 5% 0% walls 8% Proportion of envelope heat loss roof 18% doors 0.4% floor 18% walls 14% glazing 87% doors 1% glazing 49% Does not include losses from a hot water service Introduction to Module 3 Scope of the BCA Methods of Compliance Some Relevant Terms • R-Value – the ability of a material to resist heat flow – it is determined by testing • Total R-Value - the sum of the R-Values of components of an assembly – it is determined by calculation or reference e.g. refer to AIRAH Handbook Introduction to Module 3 Scope of the BCA Methods of Compliance Example of Total R-Value • R-Value is the measure of the thermal resistance of a material for a given thickness • Total R-Value is the overall performance of a building element i.e. a wall – Materials in element added together – Air films and air spaces form part of the insulating system • Materials listed in Specification J1.2 Introduction to Module 3 Scope of the BCA Methods of Compliance Some Relevant Terms • U-Value – the ability of a material to conduct heat • U-Value - the reciprocal of the R-Value – i.e. 1 / R Value Introduction to Module 3 Scope of the BCA Methods of Compliance THERMAL INSULATION Introduction to Module 3 Scope of the BCA Methods of Compliance Thermal Insulation • Insulation may be added to elements of the building fabric to achieve the required level of thermal performance • Insulation must be installed to form a consistent and continuous barrier other than at studs etc • Gaps in the barrier allow heat in or out and reduce the efficiency of the barrier Introduction to Module 3 Scope of the BCA Methods of Compliance Thermal Insulation • Must comply with AS/NZS 4859.1 (2006 amendment) • May be either reflective insulation or bulk insulation • Must be installed as specified • Must not interfere with the operation of other installations, appliances or domestic services, such as down-lights Introduction to Module 3 Scope of the BCA Methods of Compliance Thermal Insulation • Need to ensure any required airspace is provided adjacent to the reflective surface of reflective insulation • Need to maintain the thickness of bulk insulation as compression of insulation material can reduce the RValue • Note: Try to ensure that artificial cooling of internal spaces will not create condensation within adjoining elements Introduction to Module 3 Scope of the BCA Methods of Compliance ROOFS Introduction to Module 3 Scope of the BCA Methods of Compliance Roofs • The roof of a house is typically the largest element of external fabric exposed to solar radiation • Roofs and ceilings need to be insulated to achieve the required level of thermal performance • Insulation performance required will depend upon direction of heat flow Introduction to Module 3 Scope of the BCA Methods of Compliance Direction of Heat Flow • The direction of heat flow that needs to be counteracted will depend on the climate zone • The direction of heat flow is the dominant direction during typical hours of occupation of the building Introduction to Module 3 Scope of the BCA Methods of Compliance Roofs Roof assemblies must achieve the Total R-Value specified in Table 3.12.1.1 Table 3.12.1.1 ROOFS—MINIMUM TOTAL R-VALUE 2 Climate zone Minimum required Total R-Value 1 2.7 Direction of heat flow Introduction to Module 3 Altitude less than 300 m Altitude 300 m or more 2.7 3.0 Downwards 3 4 5 6 7 8 2.7 3.5 3.2 3.7 4.3 4.8 Downwards and upwards Scope of the BCA Upwards Methods of Compliance Reduced Total R-Value • In climate zones 1, 2 and 3 - the Total R-Value may be reduced if: the upper surface of the roof has a low solar absorbance value*, or the roof space is ventilated. • Low solar absorbance values are associated with light coloured roof materials* – e.g. light grey or cream. Introduction to Module 3 Scope of the BCA Methods of Compliance Typical Absorptance Values Colour Value Slate (dark grey) 0.90 Red, green 0.75 Yellow, buff 0.60 Zinc aluminium — dull 0.55 Galvanised steel — dull 0.55 Light grey 0.45 Off white 0.35 Light cream 0.30 Introduction to Module 3 Scope of the BCA Methods of Compliance Typical construction • Certain metal framed and clad roofs require a thermal break • Figure 3.12.1.1* presents Total R-Values in different climate zones for different forms of roof and ceiling construction • A significant amount of Explanatory Information is provided in Volume Two Introduction to Module 3 Scope of the BCA Methods of Compliance Extract of Figure 3.12.1.1 TYPICAL INSULATION OPTIONS FOR TYPICAL ROOF AND CEILING CONSTRUCTION Climate zones Minimum required total R-Value Direction of heat flow 1, 2 (below 300 m altitude) 2 (at or above 300 m altitude) 3 4 5 6 7 8 2.7 3.0 2.7 3.5 3.2 3.7 4.3 4.8 4.08 4.58 Downwards Downwards and upwards Upwards (c) Pitched roof with flat ceiling – Ventilated roof space Total R-Value of roof and ceiling materials 0.73 Minimum added R-Value of insulation 1.97 0.22 2.78 0.22 2.48 3.28 2.98 3.48 ROOF LIGHTS Introduction to Module 3 Scope of the BCA Methods of Compliance Roof Lights • A roof light is a skylight, window or the like installed in a roof— (a) to permit natural light to enter the room below; and (b) at an angle between 0 and 70 degrees measured from the horizontal plane • BCA treats a roof light as an opening in a roof that allows heat flow in or out – so it must be protected Introduction to Module 3 Scope of the BCA Methods of Compliance Roof Lights • The total area of roof lights serving habitable rooms and connected spaces such as corridors is restricted • Plus the aggregate area of roof lights serving a storey must be ≤ 3% of floor area • Table 3.12.1.2 presents maximum allowable thermal values for roof lights Introduction to Module 3 Scope of the BCA Methods of Compliance Table 3.12.1.2 • Sets maximum SHGC and Total U-Values for roof lights, dependent upon; the roof light shaft index, and total area of roof lights as a % of floor area served • Roof light shaft index is derived from the relationship of shaft length to the average internal opening – see over Introduction to Module 3 Scope of the BCA Methods of Compliance Roof light STEP ONE: MEASURE SHAFT LENGTH (Elevation view) 1/2 Shaft length measurement: Measured from centre of the shaft at the roof to the centre of the shaft at the ceiling level. 1/2 Roof cladding Roof light Shaft Ceiling level Wall 1/2 1/2 X STEP TWO: MEASURE AVERAGE INTERNAL SHAFT OPENING AT CEILING LEVEL, OR THE DIAMETER FOR A CIRCULAR SHAFT (Plan view) Roof light Shaft Y Average internal opening = (X + Y) / 2 STEP THREE: DIVIDE THE CENTRE SHAFT LENGTH (STEP ONE) BY THE AVERAGE INTERNAL SHAFT OPENING (STEP TWO) Roof light shaft index = Roof light shaft length / Average internal opening at ceiling level EXTERNAL WALLS Introduction to Module 3 Scope of the BCA Methods of Compliance External Walls • As with roofs, the construction of external walls is a major factor in the thermal efficiency of a building • External walls may comply by achieving a minimum Total R-value • Concessions to the minimum Total R-Value are provided in warmer climate zones Introduction to Module 3 Scope of the BCA Methods of Compliance External Walls • Table 3.12.1.3 presents options for wall construction within each climate zone • In cooler climate zones, if wall construction cannot comply – glazing in the same storey is allowed to be "over-designed" to compensate • Metal framed walls with light weight external cladding require a thermal break Introduction to Module 3 Scope of the BCA Methods of Compliance External Walls • Figure 3.12.1.3* presents typical insulation options for typical wall construction • A significant amount of Explanatory Information is provided in Volume Two Introduction to Module 3 Scope of the BCA Methods of Compliance EXTRACT OF FIGURE 3.12.1.3 TYPICAL INSULATION OPTIONS FOR TYPICAL WALL CONSTRUCTION 1, 2, 3 and 5 Climate zones Minimum required Total R-Value for walls 1.9 4 and 6 2.2 7 2.4 8 3.3 Typical wall construction R-Values (a) Weatherboard Total R-Value of wall materials Minimum added R-Value of insulation (b) Cement and metal sheet 1.73 1.49 1.79 2.83 1.99 2.89 0.55 1.35 1.65 Total R-Value of wall materials Minimum added R-Value of insulation 1.93 0.41 Total R-Value of wall materials Minimum added R-Value of insulation (d) Concrete blockwork masonry (minimum 140 mm masonry) 1.43 Total R-Value of wall materials Minimum added R-Value of insulation (c) Clay masonry veneer (minimum 110 mm external masonry) 0.47 1.85 2.75 0.53 1.37 1.17 1.87 2.77 Typical types of wall construction (a) Weatherboard Introduction to Module 3 (b) Cement sheet Scope of the BCA Methods of Compliance FLOORS Introduction to Module 3 Scope of the BCA Methods of Compliance Floors • There are separate requirements for: suspended floors - timber or concrete slab-on-ground with a built in heating or cooling system • Suspended floors must achieve a Total R-Value for heat flow in the downwards direction in climate zones 4 - 8 inclusive Introduction to Module 3 Scope of the BCA Methods of Compliance Suspended Floors • Table 3.12.1.4 (not shown) sets minimum Total R-Values • Required Total R-Values are lower if the suspended floor is enclosed • Figure 3.12.1.4* – presents typical R-Values for suspended floors Introduction to Module 3 Scope of the BCA Methods of Compliance Extract of Figure 3.12.1.4 TYPICAL INSULATION OPTIONS FOR TYPICAL SUSPENDED FLOOR CONSTRUCTION (for a floor without a floor heating system) Climate zone 4 Perimeter treatment Minimum required Total RValue 6 7 8 4 Enclosed 1.0 1.0 1.5 6 7 8 Unenclosed 2.0 2.0 2.0 2.5 3.0 (a) Suspended timber floor Total R-Value of floor materials Minimum R-Value of insulation Introduction to Module 3 0.7 0.3 0.3 0.8 Scope of the BCA 1.3 1.3 1.3 1.8 2.3 Methods of Compliance ATTACHED CLASS 10a BUILDINGS Introduction to Module 3 Scope of the BCA Methods of Compliance Attached Class 10a Buildings • A Class 10a building may include a garage, pool enclosure, etc. • A Class 10a should not compromise the thermal performance of the Class 1 building • Design options are described on the next slide Introduction to Module 3 Scope of the BCA Methods of Compliance Attached Class 10a Buildings • A Class 10a attached to a Class 1 must have either: (a) external fabric that achieves required level of performance for the Class 1, OR (b) be separated by construction that achieves required level of performance for the Class 1, OR (c) in climate zones 4 and 5 – see over Introduction to Module 3 Scope of the BCA Methods of Compliance Attached Class 10a Climate zones 4 and 5 • be enclosed with masonry walls - other than for doors and glazing, AND • be separated from Class 1 - with a masonry wall extending to a ceiling, AND • achieve a Total R-Value in the roof - equal to that required for the Class 1 • See next slide for diagrams Introduction to Module 3 Scope of the BCA Methods of Compliance Attached Class 10a Introduction to Module 3 Scope of the BCA Methods of Compliance EXTERNAL GLAZING Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.2 - External Glazing • Good design of glazing in external walls can provide the greatest gains in energy efficiency in housing • The intent is to control the amount of energy entering or leaving a building • The provisions address both external glazing and shading of glazing Introduction to Module 3 Scope of the BCA Methods of Compliance Definition of glazing • Glazing - for the purposes of Part 2.6 and Part 3.12 means: "a transparent or translucent element and its supporting frame located in the external fabric of the building, and includes a window and the glazed part of a door" Introduction to Module 3 Scope of the BCA Methods of Compliance Contributing factors • • • • • Location of the building Floor area of the storey Total area of glazing Types of frames and glass used Degree of exposure to the sun – orientation and shading considered • The likelihood of the building being air-conditioned for long periods Introduction to Module 3 Scope of the BCA Methods of Compliance Some Relevant Terms • Solar Heat Gain Coefficient (SHGC) – a measure of the proportion of solar energy (or radiation) that passes through glazing • High SHGC values - allows more solar energy into a room Introduction to Module 3 Scope of the BCA Methods of Compliance Some Relevant Terms • Total U-Value - a measure of the ability of a material to conduct heat • Low Total U-Values means the material is a poor conductor of heat – this is good Introduction to Module 3 Scope of the BCA Methods of Compliance Acceptable construction practice • Glazing provisions require: calculation of allowed values for glazing, and calculation of actual values for glazing. • For Deemed-to-Satisfy designs actual values must not exceed allowed values • Clause 3.12.2.1. provides formulae for calculations OR • You can use the ABCB Glazing Calculator Introduction to Module 3 Scope of the BCA Methods of Compliance Acceptable construction practice • Clause 3.12.2.1 – a two step process • Step 1 Use Table 3.12.2.1 to calculate allowable values for: conductance solar heat gain for the glazing in each storey of the building. Introduction to Module 3 Scope of the BCA Methods of Compliance Acceptable construction practice • Step 2 - subclause (b) Calculate actual: aggregate conductance aggregate solar heat gain of glazing in each storey • Each glazing element must be assessed individually and added to establish the aggregate value for each storey Introduction to Module 3 Scope of the BCA Methods of Compliance Step 2 – Aggregate conductance • Calculate aggregate conductance by multiplying: Area for each glazing element Total U-Value for each glazing element • Add the results for each glazing element to get the aggregate Introduction to Module 3 Scope of the BCA Methods of Compliance Step 2 – Aggregate solar heat gain • Calculate aggregate solar heat gain by multiplying: Area for each glazing element SHGC for each glazing element E (solar exposure factor) for each glazing element • Add the results for each glazing element to get an aggregate value Introduction to Module 3 Scope of the BCA Methods of Compliance Step 2 – Aggregate solar heat gain • E (solar exposure factor) can be found using Table 3.12.2.2 (not shown) • To use the Table you will need to determine: the orientation of each glazing element using Figure 3.12.2.1 – see over the P/H ratio of shading projections – using Figure 3.12.2.2 and Clause 3.12.2.2 – see over Introduction to Module 3 Scope of the BCA Methods of Compliance Step 2 – Notes • Total U-Values and SHGC's may be included on glazing element labels or obtainable from manufacturers • Total U-Values and SHGC's must be for the glass and the frame combined • Total U-Values and SHGC's must be National Fenestration Rating Council (NFRC) ratings rather than Australian Average National Conditions (ANAC) ratings Introduction to Module 3 Scope of the BCA Methods of Compliance Orientation • North orientation minimises summer sun and maximises winter sun • A glazing element is considered to face North if it faces any direction in the North orientation sector of Figure 3.12.2.1* • The orientation of other glazing elements is determined in a similar way Introduction to Module 3 Scope of the BCA Methods of Compliance Figure 3.12.2.1 Orientation Sector 22. 5°) .5°) 337 NN E( W( NN True North ( 0°) NORTH SECTOR NORTH WEST SECTOR WN W( NORTH EAST SECTOR 292 .5°) E( EN WEST SECTOR EAST SECTOR ESE .5°) 247 W( WS SOUTH WEST SECTOR ( 11 2.5 °) SSW SOUTH SECTOR °) 7.5 ( 15 ( 20 2.5 °) SOUTH EAST SECTOR SSE Introduction to Module 3 5°) 67. Scope of the BCA Methods of Compliance Shading • Shading required in order to comply with Clause 3.12.2.1 must comply with Clause 3.12.2.2 • Shading can be provided by: – external permanent projections such as a verandah or carport, or – external shading devices such as shutters, blinds or screens Introduction to Module 3 Scope of the BCA Methods of Compliance FIGURE 3.12.2.2 Measuring P and H Notes: 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. Where G exceeds 500mm, the value of P must be halved. Introduction to Module 3 Scope of the BCA Methods of Compliance Compare the results • Once aggregate conductance and aggregate solar heat gain values are calculated - compare the actual values against the allowed values for each storey • Aggregate values must not be greater than allowed values for Deemed-to-Satisfy designs Introduction to Module 3 Scope of the BCA Methods of Compliance http://www.abcb.gov.au Introduction to Module 3 Scope of the BCA Methods of Compliance BUILDING SEALING Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.3 - Building Sealing • Provisions for Building Sealing address: Chimneys and flues Roof lights External windows and doors Exhaust fans Construction of roofs, walls and floors Evaporative coolers Introduction to Module 3 Scope of the BCA Methods of Compliance Building Sealing • Limiting air leakage in and out of a building can have a major impact on the thermal performance of the building • Sealing openings, joints and gaps is an effective means of controlling unwanted internal air movement Introduction to Module 3 Scope of the BCA Methods of Compliance Deemed-to-Satisfy Provisions • Sealing provisions generally apply to Class 1 buildings and a Class 10a with a conditioned space; other than: where the only means of air-conditioning is via an evaporative cooler in climate zones 1, 2, 3 and 5 Permanent ventilation openings for gas appliances Class 10a accommodating vehicles Introduction to Module 3 Scope of the BCA Methods of Compliance Chimneys and flues • Chimneys or flues of solid fuel burning appliances (e.g. timber, coal etc) must have a damper or flap that can be closed to seal the chimney or flue • The general provisions of Part 3.7.3 "Heating Appliances" should also be considered Introduction to Module 3 Scope of the BCA Methods of Compliance Roof lights • Must be capable of being sealed if in; a conditioned space or a habitable room in climate zones 4, 6, 7 and 8 • As described above – must have: a imperforate diffuser or a weatherproof seal or an operating shutter system Introduction to Module 3 Scope of the BCA Methods of Compliance External windows and doors • Must be fitted with edge seals if in: a conditioned space or a habitable room in climate zones 4, 6, 7 and 8 • Edge seals may be compressible or fibrous strips • Requirements do not apply to external openings fitted with louvres • Compliance with AS 2047 is acceptable Introduction to Module 3 Scope of the BCA Methods of Compliance Exhaust fans • Must be fitted with a sealing device if in; a conditioned space or a habitable room in climate zones 4, 6, 7 and 8 • A sealing device includes: a self-closing damper or a filter – such as in a kitchen range hood Introduction to Module 3 Scope of the BCA Methods of Compliance Roofs, external walls and external floors • Must be constructed to minimise air leakage if part of the external fabric of: a conditioned space or a habitable room in climate zones 4, 6, 7 and 8 • Construction must incorporate internal lining systems sealed by skirting, architraves, cornices or caulking Introduction to Module 3 Scope of the BCA Methods of Compliance Evaporative coolers • Must be fitted with a self-closing damper or similar when serving: a heated space or a habitable room in climate zones 4, 6, 7 and 8 Introduction to Module 3 Scope of the BCA Methods of Compliance AIR MOVEMENT Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.4 - Air Movement • Provisions for Air Movement address: Air movement Ventilation openings Ceiling fans and evaporative coolers Introduction to Module 3 Scope of the BCA Methods of Compliance Air movement • The intent of these provisions is to: maximise the cooling effects of natural air movement facilitate internal cross-flow ventilation reduce the use of air-conditioning Introduction to Module 3 Scope of the BCA Methods of Compliance Air movement • Provisions apply to habitable rooms in Class 1 buildings in climate zones 1 to 5 • Provisions are separate to Part 3.8.5 • Table 3.12.4.1* sets minimum total ventilation opening area as a % of floor area of the habitable room based on: climate zone provision of a ceiling fan or an evaporative cooler Introduction to Module 3 Scope of the BCA Methods of Compliance Table 3.12.4.1. Climate zones 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 15% 12.5% 15% (see Note) 2 10% 5% 10% (see Note) 3 12.5% 7.5% 7.5% 4 10% 5% 5% 5 7.5% 5% 7.5% (see Note) 6, 7 and 8 Introduction to Module 3 As required by Part 3.8.5 Scope of the BCA Methods of Compliance Air movement • Table 3.12.4.1 does not apply to Class 1 buildings in REGION D – Severe Tropical Cyclone areas – subject to specific circumstances • Air movement may be provided from openings in certain adjoining rooms, including an enclosed verandah Introduction to Module 3 Scope of the BCA Methods of Compliance Ventilation Openings • The total ventilation opening area to a habitable room must be: connected by a breeze path to another ventilation opening in another room or space – OR provided by at least two ventilation openings in the same room, each being ≥ 25% of the requirement for the room Introduction to Module 3 Scope of the BCA Methods of Compliance Ceiling fans and evaporative coolers • Ceiling fans and evaporative coolers used to establish the size of ventilation openings under Table 3.12.4.1 must: be permanently fixed and have a speed controller and ceiling fans have 900mm minimum diameter Introduction to Module 3 Scope of the BCA Methods of Compliance SERVICES Introduction to Module 3 Scope of the BCA Methods of Compliance Part 3.12.5 - Services • Provisions for domestic services address: Acceptable construction manuals o AS/NZS 3500.4 or AS/NZS 3500.5 Acceptable construction practice o Insulation of services o Central heating water piping o Heating and cooling ductwork Introduction to Module 3 Scope of the BCA Methods of Compliance Services • The intent is to minimise energy lost through reticulation systems for: Air-conditioning Central heating Hot water supply • The Deemed-to-Satisfy Provisions apply to domestic services in both Class 1 and Class 10a buildings Introduction to Module 3 Scope of the BCA Methods of Compliance Acceptable construction manual • One manual is referenced • Compliance with Section 8 of AS/NZS 3500.4 OR Clause 3.38 of AS/NZS 3500.5 is Deemed-to-Satisfy P2.6.2 in regard to design and installation of a hot water supply system • Solar hot water systems in climate zones 1,2 or 3 are not required to comply Introduction to Module 3 Scope of the BCA Methods of Compliance Insulation of services • Thermal insulation for piping and ductwork must : withstand temperatures to which they will be exposed and be protected against detrimental affects of weather and sunlight Introduction to Module 3 Scope of the BCA Methods of Compliance Central heating water piping • Piping not located in the conditioned space served must be insulated to achieve a minimum Total R-Value specified in Table 3.12.5.1 • Total-R-Value depends on the: location of the piping and climate zone Introduction to Module 3 Scope of the BCA Methods of Compliance Heating and cooling ductwork • Heating and cooling ductwork not located in the building envelope must: achieve Total R-Value in Table 3.12.5.2 use AS/NZS 4859.1 insulation be sealed against air loss • Duct insulation in certain locations must be protected from dampness Introduction to Module 3 Scope of the BCA Methods of Compliance Heating and cooling ductwork • Table 3.12.5.2 Total-R-Value depends on: location of the ductwork and/or fittings climate zone type of heating or cooling system Introduction to Module 3 Scope of the BCA Methods of Compliance ALTERNATIVE SOLUTIONS Option to develop an Alternative Solution • To comply with BCA Performance Requirements some practitioners will follow Deemed-to-Satisfy Provisions • However - it’s often preferable to design something different to Deemed-to-Satisfy and to develop an Alternative Solution Introduction to Module 3 Scope of the BCA Methods of Compliance Remember the BCA structure? PERFORMANCE REQUIREMENTS MANDATORY REQUIREMENTS OR DEEMED-TO-SATISFY PROVISIONS Introduction to Module 3 ALTERNATIVE SOLUTIONS Developing Alternative Scope of the BCA Solutions OPTIONAL MEANS OF COMPLIANCE Methods of Compliance Complying with Performance Requirements • Compliance with the Performance Requirements can only be achieved by: a) complying with the Deemed-to-Satisfy Provisions, or b) formulating an Alternative Solution which (i) complies with the Performance Requirements, or (ii) is shown to be at least equivalent to the Deemed-toSatisfy Provisions; or c) a combination of a) and b) Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Design Flexibility • The BCA provides two pathways to formulate an Alternative Solution; i.e. formulating an Alternative Solution to meet the Performance Requirements, or formulating an Alternative Solution to at least equate to Deemed-to-Satisfy Provisions Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Flexibility in compliance • Either of these options can be explored to establish the most appropriate pathway for a particular Alternative Solution • A decision regarding the most appropriate pathway may be influenced by the views of the Building Control Authority Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Consultation • It is beneficial to discuss Alternative Solution with the Building Control Authority before lodging an application for approval • Also discuss the scope of supporting documentation needed to be provided • Certifier can advise on likely Assessment Methods – but should not become involved in development of the design Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance DEVELOPING ALTERNATIVE SOLUTIONS Alternative Solutions • The development of Alternative Solutions was covered in detail in Module 2 • Relevant BCA provisions can be found in Section 1 of Volume Two Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance ASSESSMENT METHODS Assessment Methods • Assessment methods were discussed in detail in Module 2 • Methods for assessing Building Solutions are listed in Clause 1.0.9 • Building Control Authority will assess compliance of Alternative Solutions • Applicant is required to demonstrate compliance with the relevant Performance Requirements Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Assessment Methods Four Assessment Methods are listed in Clause 1.0.9: • • • • Evidence of Suitability described in Clause 1.2.2 2. Verification Methods Comparison with Deemed-to-Satisfy Provisions Expert Judgement Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Evidence of Suitability Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Evidence of Suitability • Evidence of Suitability is listed in Clause 1.2.2 of Volume Two • The listed processes are generally third party mechanisms that may be used to assist either the formulation or assessment of Building Solutions Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Clause 1.2.2 – Evidence of Suitability • Registered Testing Authority report • Certificate of Conformity / current Certificate of Accreditation • Certification from appropriately qualified persons • Certification from Joint Accreditation System of Australia and New Zealand accredited body • Scientific Services Laboratory product listing • Any other form of documentary evidence Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance VERIFICATION METHODS What is a Verification Method? • Verification Method is defined as: a test, inspection, calculation or other method that determines whether a Building Solution complies with the relevant Performance Requirements • The definition allows a broad range of processes to be used to verify compliance Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Application of Verification Methods • BCA Verification Methods for energy efficiency apply to: whole Class 1 buildings whole Class 1 buildings that incorporate attached and enclosed Class 10a parts, such as attached garages • BCA Verification Methods do not apply to detached garages or to open carports Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Verification Methods • Volume Two contains two Verification Methods for energy efficiency V2.6.2.1 - Verification using a stated value V2.6.2.2 - Verification using a reference building • Both Verification Methods require the application of a thermal calculation method • Remember - other Verification Methods may be used Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance V2.6.2.1 - using a stated value • Requires a thermal calculation to show that the building's energy rating is not less than 5 stars • Software used to establish the energy rating of a house must comply with the ABCB Protocol for House Energy Rating Software – www.abcb.gov.au • Does not cover domestic services – so these must be DTS or be demonstrated to comply with P2.6.2 using another Assessment Method Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance V2.6.2.1 - using a stated value (explanatory information only) • Effects of building fixtures such as carpets, heavy curtains, reflective window coverings etc may be considered, provided the fixtures are installed and have a degree of permanency • Effects of adjoining buildings and topographic features etc may be considered, provided features have a degree of permanency Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance V2.6.2.2 - using a reference building • Allows the use of a broad range of Australian and international energy analysis software • Requires a thermal calculation to show that the cooling load and/or heating load is not greater than than that of the reference building • Specific requirements relate to respective climate zones – so check what's required Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance V2.6.2.2 - using a reference building • A Table presents thirteen minimum criteria to be used for modelling • Minimum criteria are either individually specified or equate to DTS provisions e.g. – roof pitch 18 degrees ceiling height 2.4m external walls 110mm brick-veneer glazing as per Clause 3.12.2 Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance V2.6.2.2 - using a reference building • Does not cover domestic services –must be DTS or be demonstrated to comply with P2.6.2 using another Assessment Method • Requires two computer modelling runs; one to set the target one to demonstrate that the design is equal to or less than the target Introduction to Module 3 Developing Alternative Scope of the BCA Solutions Methods of Compliance Administrative Matters Administrative Issues • All State/Territory jurisdictions have administrative provisions that relate to the design and construction of buildings • Energy efficiency is an issue for which specific administrative process may exist; e.g. energy efficiency assessors may be required to be accredited • Practitioners need to be aware of relevant processes and ensure they comply • Alterations, additions and renovations Any Questions?