The lecture was provided to 3-4 years students doing the Course Mech4460 - Energy & Environment at the University of Queensland. The aim was to introduce energy efficiency and energy efficiency regulations in the built Environment.

1. BCA Section J
Energy Efficiency
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2. Overview
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State Legislation & BCA changes in 2013
BCA Hierarchy
Intent of BCA section J
Definitions
BCA DTS review of Building Fabric
BCA DTS review of Glazing
BCA DTS review of Building Sealing
Mechanical
Electrical
Hydraulics
Introduction to JV3 energy modeling
Exercises

3. State Legislation
Legislation varies in each state, the BCA Section J requirements where
included for all new building designs from the 1st May 2005 for all states
and territories in Australia. NT has still not legislated the use of BCA
section J. The first major stringency increase of the BCA section J
occurred in 2009 for the 2010+ versions.
The 2013 version of the BCA Section J applies to all buildings designs
from the 1st May 2013.
Substantial changes in 2012 from 2013 are:
> Internal glazing and glazing to non-conditioned spaces must be
compliant
> Fan motor power energy efficiency targets required a further 30%
improvement
> Direct electric heating prohibited in most applications
> JV3 energy modeling approach is becoming more widely used due to
the restriction on designs of the Deemed-to-Satisfy provisions

4. BCA Hierarchy
We will
cover this
&….
An Intro
to JV3
energy
modeling

5. Intent of BCA section J
To reduce
Green House
Gas Emissions
“Buildings have the greatest potential to improve performance”

6. Intent of BCA section J
> 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
> The extent of specific requirements will generally vary
depending on the use of the building and the climate zone in
which it is located
> BCA requirements primarily address base building in relation
to:
> Heat flow-in and out of a building through the building
envelope, and
> Services-that use energy e.g. lighting, air-conditioning and
hot water

7. Intent of BCA section J

8. Intent of BCA section J

9. Intent of BCA section J

10. Definitions
Air-conditioning
> A service that actively heats or cools a space in a building in order
to provide a suitable environment for the building occupants
Conditioned space
> Space within a building where the environment is likely to be
controlled by air-conditioning but does not include –
> (a) a non-habitable room of a Class 2 building or a Class 4
building in which a heater with a capacity of not more than
1.2kW provides the air-conditioning; or
> (b) a space in a Class 7, 8 or 9b building where the input
power to an air-conditioning system is not more than 15
W/sqm

11. Definitions
Envelope (Very Important)
> Parts of the building’s fabric
that separates a conditioned
space from the exterior of the
building or a non-conditioned
space

12. Definitions
Further Explanation of the Envelope
Plant room ceiling is not required to be
insulated as it is not part of the envelope
Occupied space is required to have the
ceiling insulated when below a plant
room or non-conditioned space
Plant Room
Occupied space
Occupied space

13. BCA DTS review of Building Fabric
The adjacent
table is an extract
from the BCA.
This table applies
to roofs and
ceilings
The table
specifies the
minimum total
averaged R-value
for the
construction

14. BCA DTS review of Building Fabric
Walls (See J1.5)
The table adjacent shows the calculations
required to determine a total R-value for a
particular construction.
If there is a mixture of constructions across a
façade the average total of these will determine the
compliance of the façade.

15. BCA DTS review of Glazing (Part J2)
Glazing -for the purposes of Section J2 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“

16. Glazing Performance: “U” & “SHGC”
The BCA J2 Provisions Consider:
> Heat Conduction through glazing driven by a difference in temperatures… U Value
> Solar Radiation through glazing into building…...Solar Heat Gain Coefficient (SHGC)
Glazing performance is “whole of window” and includes framing.
Can be obtained from A) manufacturer, B) www.wers.net/commercial/certified-products
or C) calculated.

17. BCA DTS review of Building sealing
Part J3 Building Sealing
Construction of roofs, ceilings, walls and any opening such as a
window, door or the like, must be constructed to minimize air
leakage.
A perforated ceiling in this
application may not comply
with J3, even if there is
insulation applied in
compliance with J1.

18. Architecture: Energy Efficiency Cont.
PART J3 BUILDING SEALING
> J3.1 Intent
> All openings within the building that allow escape of energy are to be
considered and treated so as to reduce energy loss
> J3.4 Windows and Doors
> Requires seals to be fitted to doors, openable windows, etc. forming part of
the external fabric of a habitable room
> Seals on louvre doors, louvre windows or other such openings, are
required.

19. Architecture: Energy Efficiency Cont.
> Building envelope to be fully sealed against
air leakage – future consideration of making
building leakage testing mandatory as in the
UK
> Draft protection devices to be fitted to the
bottom edges of external swing doors
> Provision for airlocks, apply to any entrance
J3.5 Exhaust Fans
> Requires an exhaust fan to be fitted with a
sealing device such as a self-closing damper
J3.7 Evaporative Coolers
> Require an evaporative cooler to be fitted
with a self-closing damper.

20. Mechanical: Energy Efficiency
PART J5 AIR-CONDITIONING & VENTILATION SYSTEMS
> Looks at system design and control, Fan and pump energy
and the allowances for outside air.
> J5.2 Air-conditioning and Ventilation Systems
 The air conditioning of a Class 3 sole occupancy unit
must cease if an external door to a balcony, patio or
courtyard is left open.
 Minimum Pump and fan Power efficiency requirements
> Variable air flow systems to have VSDs
> Economy cycle threshold lowered and exemptions
> The over-supply permitted of outside air has been
reduced is 120%. NOTE conflict with the GBCA 150%
OA increase to get minimum green points in IEQ-1
> Systems to have fully insulated ducting on supply air
side
> Return air ducting in ceiling void of a conditioned space
does not need insulation

21. Mechanical: Energy Efficiency Cont.
> J5.4 Heating and Cooling Systems
> Separate pump allowances for chilled
water, condenser water and heating water.
> Minimum threshold for variable speed
pumps 3 kW – i.e. below 3kW pump power
no VSD is required
> Provisions for heating a space, the
requirements for a heating systems to be
other than a direct electric heating. Also, oil
is limited to locations without reticulated
gas.
> Fixed space heating appliances installed
outdoors must have automatic controls.
> Insulation on duct and pipe services must be to
AS/NZS 4859.1 and is specified in terms of
material R-value. Refrigerant and steam piping is
included.

22. Electrical: Energy Efficiency
> J6.2 Interior Artificial Lighting
> Amended so that (a) now applies in sole-occupancy
units in a Class 2 building or a Class 4 part while (b)
applies to all other buildings
> Consequently, Table J6.2a has been removed and
other tables amended
> Class 2 and Class 4 part are now required to meet 5star energy rating
> Some illumination power densities have been
increased while others reduced. E.g. Laboratory
is 12W/m² instead of 15W/m²
> As part of the increased energy efficiency
stringency, the exception for small shops in (b)(i)
has been removed
> Internal light fitting transformers or ballasts to be
electronic type only
10 July 2010

23. Electrical: Energy Efficiency Cont.
> J6.3 & J6.4 Interior Artificial Lighting and Power Control
> Light switches for single lighting zones such as in an auditorium, theatre,
swimming pool or sporting stadium is allowed to be a single switch, all other
areas of buildings are to have zone controlled lighting.
> The allowable area of a lighting zone controlled by one switch is been limited
to 250 m2 in Class 5 (office) buildings and Class 8 laboratories
>
95% of buildings other than class 2, 3 and
parts of class 4, of more than 250m² shall be
controlled by a time switch or occupancy
sensor.
>
J6.4(a) Decorative and Display lighting shall
be separately switched by time switch if the
lighting exceeds 1KW.
>
All lighting systems have maximum power
density values that are specified in the BCA.

24. Hydraulic and Mechanical: Energy Efficiency
PART J7 HW SUPPLY & SWIMMING POOL & SPA POOL PLANT
> Provisions requiring swimming pools and spa pools to use energy
efficiently and also to not be heated by electricity.
> Additionally, a time switch must be provided for controlling the
circulation pump and heated swimming / spa pools must be
covered when not being used.

25. All Discipline: Energy Efficiency
PART J8 ACCESS FOR MAINTENANCE & FACILITIES FOR
MONITORING
> J8.3 Facilities for Energy Monitoring
> Provision of a means of measuring the energy use of the
various services.
> Buildings over 2000m2 are to have individual metering for
Lighting, power, HVAC, hydraulics and other major systems.

26. JV3 - Energy Modeling
Comparing the Method of Assessment
A – Architecture
B – Building Services
C – Compliance

27. JV3 - Energy Modeling
Energy models form the IES-VE software

28. JV3 - Energy Modeling
Results tables
1. Results tables – what is sometimes presented – what should be presented
Building
Services – Mech, Elec Hydra
Annual Energy Consumption (MWh)
Time
Period
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Total
Reference
Proposed
Building
Building
78.1803
51.3554
69.8147
46.2047
70.0583
43.1365
59.9688
34.5594
54.5476
30.4192
45.5895
27.8947
46.0715
28.8246
49.1038
28.8666
54.0059
28.61
62.1816
34.7663
68.5068
41.5262
74.6208
46.9102
732.6497 443.0738
OR
Baseline
Baseline
Proposed
Baseline
Proposed
Proposed
Lighting
Equipment
Heating, cooling, and Ventilation - packaged
unit
Lifts
Hot Water
Total - MWh
Conversion to MJ - factor
Total MJ
Conversion to Kg CO2/yr - factor
MWh
1.5222
1.4642
MWh
1.5222
1.4642
MWh
1.5222
1.4642
2.4568
0
1.3705
6.8137
3.6
24.52932
0.0548
2.4568
0
1.3705
6.8137
3.6
24.52932
0.0548
2.2892
0
1.3705
6.6461
3.6
23.92596
0.0548
Kg CO2/yr
Assessed area (m2)
kWh/m2
1.344
60
114
1.344
60
114
1.311
60
111

29. Energy Modeling – of building massing

30. Energy Modeling – of building massing

31. Energy Modeling – of building massing

32. Self learning Exercises
1. In your own words, describe the meaning of R-value?
2. What is the difference between R-value and Total R-value?
3. What wall construction that forms part of the envelope would not
require additional insulation?
4. What needs to be considered when selecting thermal insulation?
5. What needs to be considered when installing reflective insulation?
6. What needs to be considered when installing bulk insulation?
7. In your own words describe the meaning of U-value?
8. What is the difference between SHGC – Solar Heat Gain Coefficient and the SC - Shading co-efficient?
9. Determine why HVAC systems have different zoning – how should
these zones be arranged?
10. Lighting systems such and LED and compact fluorescence are more
efficient – can they be used in all situations?
11. Why would climate zones 1 & 2 be allowed to use direct electric
heating?

33. Self learning Exercises
Some Heat load calculations in a Space
1. From the data provide, calculate the grand total heat load in the
room

34. Self learning Exercises
Some Heat load calculations in a Space
1. Room is a Cube with a flat roof – 4m x 4m x 3m high – all elements
U-value of 0.5 W/m2 K
2. Room contains 2 people – 75W sensible & 55W Latent
3. Room contains 1 flat screen TV (350W), Computer (200W) and
modem (5W)
4. Room has one large window in the north facing wall – 2m wide x
1.8m high and no shading devices – standard domestic single
glazed window
5. Outside air temperature is 37 C, inside is to be kept at 24 C
6. Room has 2-12W LED lights
7. Infiltration of air into the space occurs at a rate of 0.25 air changes
per hour
Calculate the grand total heat gain in the space
How do you reduce this heat gain? What are some ideas?