In a piece of very welcome news, the Australian Building Codes Board (ABCB) is proposing a revision to the 2016 version of the National Construction Code (NCC) which will fundamentally change the way that we certify multi-residential towers against Section J. And not a moment too soon!
The words ‘Existing Verification Method JV3 – Class 2 buildings included in the application provision of the Verification Method as a means to comply with JP1’ has been like music to my ears.
The significance of this is huge. It means that instead of the painstaking NatHERS assessments whereby each apartment is modelled in isolation, potentially you will soon be able to instead model apartment towers in the same way as commercial developments – a holistic, whole-building approach.
This may not seem like a big deal, but honestly, it is great news for all involved in the design process of these towers. In essence, apartment developments are one of the more efficient ways to provide housing from an energy consumption perspective, but the current NatHERS methodology seriously penalises them as it was originally designed for stand-alone houses. Isolated apartment modelling commonly results in the need to install multiple glass specifications across one residential tower due to the site specific idiosyncrasies (for example shading from adjacent structures, varying wind loads and solar exposure). The outcome is often disjointed aesthetics and issues with glass procurement, not to mention potential confusion during the installation.
Undoubtedly the concept that each individual apartment meets the same minimum energy standard is an ideal situation, but it makes no allowance for the actual reality of how hard this is to achieve. Of course roof apartments perform worse than mid-floor due to their increased level of exposed fabric, but that shouldn’t then push the specification of the whole façade, which would need to be done to keep the aesthetics consistent. This proposed whole-building approach is more in line with the energy targets set by other countries around the world for multi-residential towers and I welcome it with open arms.
However, I don’t think the ABCB have got it 100 per cent right…yet. There are proposed changes to the modelling methodology for residential towers only, which would seem to allow an apartment tower in Sydney with 80 per cent of its façade glazed (basically a glass box), to comply with clear glass and no solar control. The solar loads penetrating into a western orientation apartment would be huge and energy consumption would be off the chart, not to mention the impact on thermal comfort.
The good news is that the NCC 2016 is in its draft format and the ABCB are calling to industry for feedback (you’ve got until August 3 to provide comment). This proposed changes to Section J don’t deal will the numerous issues around the quality of apartments, and the JV3 process is far from perfect, but I really feel that this is definitely a step in right direction.
The opportunity may have already been missed for this to impact in Melbourne, but with the predicted future growth in the other major cities, now is certainly the time for change.