How do new NatHERS star ratings impact residential construction costs and design strategies for builders in South Australia?

New NatHERS 7-star ratings significantly increase construction costs for South Australian builders, primarily due to enhanced insulation requirements for walls, ceilings, and floors, higher performance glazing, and improved draught sealing. Design strategies must prioritise passive solar principles, optimising dwelling orientation and window placement for local climatic conditions. Builders are utilising more efficient hot water systems and renewable energy technologies like solar PV. This necessitates greater collaboration with energy assessors early in the design phase to minimise costly retrofits and ensure compliance, impacting material selection and labour. The shift also drives innovation in building envelopes and sustainable material sourcing.