7-Star NatHERS BASIX NSW 2026: Complete Guide to Thermal Performance Compliance 7-Star NatHERS BASIX NSW 2026: Complete Guide to Thermal Performance Compliance Quick Answer (40-60 words): From May 2024, all new NSW homes must achieve a minimum 7-star NatHERS rating under BASIX th... 7 star rating BASIX NSW building regulations energy efficiency nathers-certificate thermal performance Jul 4, 2026