How can Australian home builders cost-effectively achieve a 7-star NatHERS rating for new residential projects?

To cost-effectively achieve a 7-star NatHERS rating, Australian home builders should prioritise passive design principles from the outset. This includes optimising orientation for solar gain in winter and shading in summer, along with strategic window placement and sizing. Utilising standard, readily available insulation products for walls, ceilings, and floors to exceed minimum R-values is crucial. Specifying high-performance glazing, such as low-e glass or double glazing, for key windows also provides significant energy efficiency improvements. Minimising thermal bridging and ensuring good air sealing will further enhance performance without substantial cost increases. Finally, choosing light-coloured roofing in warmer climates reduces cooling loads, contributing to a better rating economically.