Building Code of Australia

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Building Code of Australia
Training Program
MODULE THREE
Understanding Energy Efficiency
Provisions for Class 1 and 10
Buildings
Content of Module 3
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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?
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