Part J BCA 2011

Part J BCA 2011: Summary of Changes

Aug 24, 2011 | Green Rate

There are only minor changes to Part J in BCA 2011. Sole-occupancy units of a Class 2 and 4 building have moved from 5-Star to a 6-Star average, in line with the new 6-Star requirements for Class 1 homes. In addition, there have been updates to the provisions for ceiling fans, building sealing for climate zone 5, electric heating, and artificial lighting allowances. Previously, major changes to Part J in BCA 2010 saw increased stringency in glazing and insulation provisions. These areas have been left relatively untouched this time round. Green Rate prepares Part J reports in accordance with BCA 2011 for all types of buildings right across Australia. A summary of changes to BCA Part J in 2011 is listed below.

6-Star for SOU’s (BCA Part J-0):

- Sole-occupancy units (SOU) of a Class 2 building or a Class 4 part must achieve an average of 6 stars, with each individual unit (if more than one) having a minimum of 5 stars.
- Other building Classes and Class 2 common areas must comply with all relevant parts of BCA Section J as per usual.

Ceiling Fans (BCA Part J-0.3):

- New provisions for ceiling fans in sole-occupancy units of a Class 2 building or a Class 4 part. These include the requirement for fans to be permanently installed, have a speed controller, and be of a minimum size based on floor area.

Building Sealing for Climate Zone 5 (BCA Part J-3):

- Climate zone 5 added to the locations in which habitable rooms must have window and door seals, self-closing dampers on exhaust fans and evaporative coolers, roof lights must be sealed, and roofs, walls and floors constructed to minimise air leakage.

Air-conditioning & Ventilation Systems (BCA Part J-5.2):

- Provision for maximum fan power now applies to miscellaneous exhaust systems that have an air flow greater than 1000 L/s. Small un-ducted air-conditioners are now exempt from this requirement.

Electric Heating (BCA Part J-5.4):

- Electric heaters are now included as an acceptable source of space heating if gas is not available to the property. Maximum sizes apply.

Artificial Lighting & Power (BCA Part J-6):

- Maximum lamp power densities now apply to Class 2 sole-occupancy units and a Class 4 part. Base allowances are 5 W/m² indoors, and 4 W/m² on a balcony or verandah.
- Halogen lamps must be separately switched from fluorescent lamps in Class 2 sole-occupancy units and a Class 4 part.
- Electronic type transformers and ballasts not mandatory.
- Some changes to power and illumination allowances
- Separate switching of artificial lighting in natural lighting zones now applies to all applicable buildings with a floor area over 250 m².

Hot Water Supply (BCA Part J-7):

- Provisions for hot water supply systems removed for Victoria.


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