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ENERGY EFFICIENCY AWARENESS SEMINAR 2010 Building Code of Australia Regulatory Measures Commencing 1 May 2010. PURPOSE. To provide an overview of the changes to the energy efficiency provisions in the Building Code of Australia 2010 (NT variation)
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ENERGY EFFICIENCY AWARENESS SEMINAR 2010 Building Code of Australia Regulatory Measures Commencing 1 May 2010
PURPOSE To provide an overview of the changes to the energy efficiency provisions in the Building Code of Australia 2010 (NT variation) On 1st May 2010, energy efficiency requirements will be increased: New homes & extensions (Class I and 10 buildings) will move from 3.5 stars to 5 stars equivalent Apartments/flats and caretakers residences (Class 2 and 4 buildings) will move from currently no stars to 3.5 stars equivalent
CONTENT • Background • Building Code of Australia structure • Session 1 - Energy efficiency measures for houses and garages • Break • Session 2 - Energy efficiency measures for apartments, flats and caretaker’s residences
BACKGROUND • For housing - NT adopted 3.5 star measures in 2003 • BCA 2005 introduced 3.5 stars apartments and flats • BCA 2006 increased the stringency to 5 Stars • The NT is now adopting 5 star as 1 May 2010 • COAG proposed new 6 star provisions and increased stringency for commercial buildings for BCA 2010 • Territory has not adopted • Further consideration after 5 star commences
Objective Guidance Functional Statement Mandatory Performance Requirements Building Solution Methods ofachievingcompliance DTS Provisions Alternative Solution Documentary Evidence Verification Method Assessment methods Comparative Analysis Expert Judgement BCA HIERARCHY
5 STAR ENERGYEFFICIENCY PROVISIONS BCA VOLUME TWO HOUSES
BUILDING CODE OF AUSTRALIA OBJECTIVE The Object is to reduce greenhouse gasemissions by efficientlyusingenergy FUNCTIONAL STATEMENT To reduce greenhouse gasemissions, abuilding,includingits domestic services, is to becapable ofefficiently using energy PERFORMANCE REQUIREMENT A buildingandits domestic servicesmusthave alevelof thermalperformance and features to facilitate the efficient use of energy forartificialheating andcooling appropriate to the function and use of the building etc………….
ZONES APPLICABLE Climate zone 1 Climate zone 1 OLD NEW Climate zone 3 Climate zone 3
BCA VOLUME TWO SCOPE Five distinct aspects addressed: 1. Building Fabric • Thermal Insulation • Roof • External Walls • Floors 2. Glazing 3. Building Sealing 4. Air Movement 5. Domestic Services
THERMAL INSULATION • Comply with AS/NZS 4859.1 • Needs to abut or overlap adjoining insulation • Needs to form a continuous thermal barrier • Abuts supporting members such as rafters, purlins, noggings, joists and the like • Must be installed so as to not affect the safe and effective operation of a domestic service or fitting
BCA EXPLANATORY INFORMATION • The BCA & Guide contain explanatory information • on possible increased risk if inappropriate solutions are • chosen by designers or builders. • These include: • Fire resulting from insulation being close to downlights • Condensation damage (See CSIRO & DEWHA publications) • Plaster sagging under the weight of insulation & lights
THERMAL INSULATION PRINCIPLE OF R-VALUES • R-Value or material R-Value is the thermal resistance of an individual building material or component • Total R-Value is the sum of all the R-Values of individual components in a composite building assembly e.g. roof
THERMAL INSULATION PRINCIPLE OF R-VALUES • R-Value or material R-Value is the thermal resistance of an individual building material or component • Total R-Value is the sum of all the R-Values of individual components in a composite building assembly e.g. roof R-Value or material R-Value Total R-Value
Metal frame Lining Cladding Insulation Heat transfer area THERMAL INSULATION PRINCIPLE OF THERMAL BREAK • Thermal break - A thermal break restricts the conductance of heat via metal framing members of: • Roofs • Walls
Metal frame Lining Thermal break Cladding Insulation Heat transfer area THERMAL INSULATION PRINCIPLE OF THERMAL BREAK • Thermal break - A thermal break restricts the conductance of heat via metal framing members of: • Roofs • Walls
THERMAL INSULATION PRINCIPLE OF THERMAL BREAK • Thermal breaks for Roofs and Walls can be: • Timber - Minimum 20mm thick OR • Expanded polystyrene strips - 12mm thick OR • Compressed bulk insulation providing a minimum R-Value of 0.2
ROOFS CLIMATE ZONE 1 & 3 INSULATION CurrentNew 3.5 Star 5.0 Star Total R-Value 2.2 Total R-Value 2.7 Total R-Value is increased by 0.5
ROOFS Location of insulation Insulation can be added at the roof sheeting level or ceiling level or a combination of both Concessions The Total R-Value of a roof may be reduced by 0.5 for each: • Light Coloured Roof - The dwelling has a light coloured roof installed e.g. zincalume, galvanised, light grey, off white, light cream or the like • Ventilated Roof Space - The design of the dwelling has: - a pitched roof; and - a flat ceiling; and - a ventilated roof space
ROOFS Required Total R-Value 2.7 Light coloured roof concession - 0.5 Ventilated pitched roof concession - 0.5 Adjusted Total R-Value = 1.7
ROOFS DOWNLIGHTS & EXHAUST FANS • Ceiling insulation must comply with the minimum clearances as specified by the wiring rules AS/NZS 3000 extract
ROOFS DOWN LIGHTS AND EXHAUST FANS • The minimum clearances as specified by the wiring rule will result in a loss of insulation • A reduction of the area of insulation that does not exceed 1% of the ceiling area requires no change • A reduction that exceeds 1% requires an increase in the R-Value over the rest of the ceiling as per the BCA
ROOFS DOWN LIGHTS AND EXHAUST FANS
ROOFS ROOF LIGHTS • Roof lights area: • If 1.5% of room floor area - no requirements(no change) • Can now go up to 10% of room floor area BUT • Cannot exceed 3% of the floor area of the storey (no change) • Increase thermal performance depending upon size of each roof light & length of light shaft
ROOFS Roof light 1/2 1/2 Roof cladding Shaft length L Roof light Shaft Ceiling level Shaft diameter O Roof light shaft index = L O ROOF LIGHTS • Desirable outcome: • Long shaft OR • Small diameter OR • Higher performing roof lights
ROOFS SUMMARY • Increase of 0.5 in Total R-Value • Light coloured & ventilated roof concessions • Thermal break requirements • Higher R-Value ceiling insulation where downlights and exhaust fans exceed 1% • Increased stringency of roof lights
EXTERNAL WALLS CLIMATE ZONE 1 & 3 INSULATION CurrentNew 3.5 Star 5.0 Star Total R-Value 1.4 Total R-Value 1.9 This is an increase in the total R-value of 0.5
EXTERNAL WALLS Solutions for climate zone 1: • Insulate to Total R-Value of 1.9 • Reduce to R1.4 with slab-on-ground • Shading options • For sheet cladding construction • For high mass walls (not less than220 kg/m2)
EXTERNAL WALLS SHADING OPTIONS - CLIMATE ZONE 1 ONLY Sheet cladding (metal, cement, weather board): • Reflective insulation e.g. reflective foil laminate, foil bonded to batts or the like AND • Slab-on-ground AND • Shading at 15° projected from the floor to underside of eave or gutter (e.g. 2360mm wall height will require a min 750mm overhang based on a 22° roof pitch)
EXTERNAL WALLS SHADING OPTIONS - CLIMATE ZONE 1 ONLY Masonry with not less than 220 kg/m2 of wall: • Nth & Sth orientation 15° projected from the floor to underside of eave or gutter (e.g. 2360mm wall height will require a min 750mm overhang based on a 22° roof pitch) • All other orientations 45° projected from the floor (e.g. 2360mm wall height will require a min 2000mm overhang based on a 22° roof pitch)
EXTERNAL WALLS E, W, NE, SE, NW & SW North & South only
EXTERNAL WALLS • Solutions for climate zone 3: • Insulate to Total R-Value of 1.9 • Reduce to R1.4 with slab-on-ground
EXTERNAL WALLS SUMMARY • Increase of 0.5 in Total R-value (R1.4 to R1.9) • Reduced to R1.4 with slab-on-ground • Other options for climate zone 1: • Masonry wall: insulate & shade • Sheet cladding wall: foil,slab-on-ground & shade • Again, thermal breaks required forsome metal framed walls
FLOORS Climate Zones 1 and 3 No insulation requirements
GLAZING • 3.5 Star glazing was based on % of glazingto floor area with only north consideration • 5 Star glazing sets an allowance for conductance & solar heat gain taking into account the orientation, floor type & air movement rate • For compliance there are two calculations (conductance and solar heat gain) which considers each window and glass door; their orientation, thermal performance & shading
GLAZING • 3.5 Star glazing was also based on generic glass and frame systems whereas 5 Star is based on the glass & frame combined thermal performance • Also shading which can take the form of an eave, awning, veranda, carport or permanent external shading device e.g. shutters, blinds, screens etc • The ABCB has developed Glazing calculators (Excel 2003 & 2007) to assist in performing the calculations and determining compliance
IMPORTANT TERMINOLOGY 25OC 35OC Conductance Insulation: R-Value Glazing: U-Value U-Value for clear glazing 7.9 U-Value for best glazing 2.1 Solar Heat gain SHGC for clear glazing 0.81 SHGC for best glazing 0.21 GLAZING http://www.wers.net
GLAZING EXAMPLE – INITIAL DESIGN
GLAZING EXAMPLE – WITH LIGHT TINT GLASS
GLAZING EXAMPLE – WITH WERS SUPER TINT GLASS
BUILDING SEALING • No change from what is currently required • Applies to conditioned spaces and requires: • Roof light being sealed or capable of being sealed • Openings (including windows and external doors) having edge seals • Exhaust fans fitted with self closing dampers or a high density filter • Internal lining systems sealed at all junctions
AIR MOVEMENT • No Change from what is currently required • Habitable rooms to have ventilation openings to allow air movement to limit artificial cooling • Opening sizes are a percentage of the area of the habitable room’s floor • Ventilation openings percentages: • Climate zone 1 15% of floor area without fans 12.5% of floor area with fans • Climate zone 3 12.5% of floor area without fans 7.5% of floor area with fans
AIR MOVEMENT Openings providing ventilation to a habitable room in climate zones 1 & 3 must either: 1. Connect a ventilation opening to another in another room via a breeze path- • passing through not more than two opening in an internal wall each opening having an area of not less than 1.5 m2; and • have a distance along the breeze path between ventilation openings of not more than 20m OR 2. Provide a minimum of two ventilation openings in the same habitable room- • with each ventilation opening having an area of not less than 25% of the required area
AIR MOVEMENT To qualify as a fan it must: • Be permanently fixed to the ceiling • Have a blade rotation diameter of at least 900mm • Have a speed controller
SERVICES • No Change from what is currently required • See AS/NZS 3500.4 or .5: • Cold water supply pipe - insulate last 500mm to achieve minimum R-Value of 0.3 • Hot water supply pipe - insulate last 500mm to achieve minimum R-value of 0.3 • External pipes from the water heater to primary kitchen sink to achieve a minimum R-Value of 0.3 • Does not apply to Solar hot water heaters in the NT
Objective Guidance Functional Statement Mandatory Performance Requirements Building Solution Methods ofachievingcompliance DTS Provisions Alternative Solution Verification Method Comparative Analysis Assessment methods Documentary Evidence Expert Judgement ALTERNATIVE SOLUTIONS • So far we have covered the BCA Deemed-to-Satisfy Provisions. They are one way to comply. • Alternative ways to comply are: • A Verification Method: A NatHERS rating of 5 star for the dwelling • Expert Judgement: Peer review • Note that the domestic services provisionsstill apply
ALTERNATIVE SOLUTIONS Verification Method: • Computer software - more flexible solution • NatHERS approved software • Achieve a 5 star rating • DEWHA Protocol for Assessor Accrediting Organisations • No NT registration • AccuRate Training in April
ALTERNATIVE SOLUTIONS Expert Judgement: • Free running houses • Queensland Peer Review Process • NT recognition of Queensland Experts • Private contractual arrangements
END OF SESSION 1 - HOUSING ANY QUESTIONS? www.nt.gov/lands/building
3.5 STARS ENERGYEFFICIENCY PROVISIONS SESSION 2 - BCA VOLUME ONE APARTMENTS, FLATS AND CARETAKER’S RESIDENCE
BCA VOLUME ONE SCOPE Eight distinct aspects addressed: 1. Building Fabric (similar items to Housing) 2. Glazing (similar to Housing) 3. Building Sealing (similar to Housing) 4. Air Movement (similar to Housing) 5. Air-Conditioning & Ventilation 6. Artificial Light & power 7. Hot Water Supply (similar to Housing) 8. Access for Maintenance