Today, most Australian design teams will have experienced the post-2010 industry shift from using the BCA Section J calculators to assessing the façade design ‘allowance for glazing’ by adopting the JV3 alternative energy modelling pathway.

Through this alternative pathway, we have become accustomed to a more flexible approach of ‘trading off’ performance elements of the envelope to ‘outperform’ a theoretical reference design. While this has brought some freedom to designs, in particular more glass (by area), it carries a very large caveat; the reference design…