Proposed Changes to BCA 2011 – Volume 2 (Housing Provisions) (Nat)

This information sheet has been prepared based on the pre-publication draft of BCA 2011.

The 2011 editions of the Code will introduce various changes to both Volume 1 for Class 2 - 9 buildings and Volume 2 for Class 1 and 10 buildings (the Housing Provisions).

The main changes relate to the classification of buildings, accessibility, and timber framing requirements due to the BCA now referencing the revised Australian Standard for residential timber construction.

In addition, for Victoria and Western Australia, the 6-star energy efficiency provisions will be adopted under Part 3.12 for Class 1 dwellings and Part J for Class 2 apartments.

The specific changes to Volume 2 (Housing Provisions) include:

• a new referenced Australian Standard for masonry in small buildings (AS 4773)
• a new performance provision for private bushfire shelters that requires among other things the consideration of material used to construct a shelter, structural and fire loads, topology and distance between the shelter and fire hazards. Also the size of the potential fire source, wind loadings, external and internal signage are considered
• clarification that the nominal size of aggregate in concrete is 20mm maximum
• new explanatory information on compacting concrete under Part 2.3.2 ‘Concrete and Reinforcing’
• a note under figure 3.3.1.1 in relation to unreinforced masonry clarifies that flat ceilings may act as lateral support to walls
• inclusion of AS 1562.1 as the acceptable construction manual under part 3.5.3 ‘Wall Cladding’
• a new explanatory diagram and information under figure 3.8.2.1 in relation to measurement of acceptable ceiling heights
• a new explanatory note under 3.9.2.2 ‘When balustrades or other barriers are required’, that notes it is deemed possible for a person to fall through an openable window when a 125mm sphere is able to pass through the window opening
• changes to the provisions under ‘Balustrades and other barrier construction’ that exempt a window serving as a barrier from the loading forces requirements in accordance with AS/NZS 1170.1
• new explanatory information that a windowforming part of a barrier is not requiredto comply with the  AS/NZS 1170.1 in relation to structural design actions. However, a window serving as a barrier must comply with the glazing assembly provisionsof AS 2047 or AS 1288. These provisions consider the wind loading on the glass and human impactrequirements
• explanatory information in relation to a window forming part of a barrier, that notes a windowsill between 150 mm and 760 mm above the floor isdeemed to facilitate climbing
• explanatory Information under the building fabric thermal insulation provisions in relation to the installation of insulation to ensure it does not interfere with the safety or performance of domestic services
• change to the explanatory note in relation to the compression of bulk insulation that states the R-Value will be reduced if insulation is compressed
• a new note under the explanatory information in relation to external glazing for energy efficiency that the provisionsassume that internal windowcoverings will be installed for privacy reasons, and that this assumption is already incorporated in the allowances for glazing.
• new explanatory information in relation to the term ‘winter access’ that it refers to solar gains to offset conducted heat losses and the impact of shading that it considers solar heat gain to be beneficial or detrimental based on seasonal variation
• removal of the requirement under artificial lighting for the purpose of energy efficiency where lamps are used that have a transformer or ballast, that the transformer or ballast must be of the electronic type

Members wanting to find out more these changes and about the new National Construction Code can attend seminars being arranged by the Australian Building Codes Board in your state. For more information on the seminars go to the ABCB webpage.

HIA members can contact HIA Building Services staff on hia_technical@hia.com.au or call 1300 650 620 to find out more about changes to BCA 2011 in your state.

Disclaimer: The above is intended to provide general information in summary form. The contents do not constitute specific advice and should not be relied upon as such. Formal specific advice should be sought by members with respect to particular matters before taking action.  ABN 99 004 631 752