BASIX Certificates 

The Building Sustainability Index (BASIX) is a scheme designed to reduce greenhouse gasses and water consumption. It was introduced by the NSW State Government.

A BASIX Certificate is required to be lodged with all Development Applications (DAs) or applications for Complying Development Certificates (CDCs) proposing new detached and single attached houses as well as some alterations and additions to residences. The BASIX Certificate requires that houses reduce water consumption by 40% and energy consumption by 25%.

The following activities need to obtain a BASIX Certificate:

  • New single dwellings and dual occupancy 
  • New boarding houses, guest houses, hostels, lodging-houses and backpacker accommodation under 300m2 
  • All new residential dwellings, including villas, townhouses and low-rise, mid-rise and high-rise developments in NSW 
  • Extensions/modifications to living areas or wet areas to existing dwellings (where works are valued @ over $50,000) 
  • New pools & outdoor spas (in excess of 40,000L) 

A BASIX Certificate is only required where the works above require a DA or CDC. BASIX requirements do not apply to:

  • New garages/carports 
  • New outdoor/open structures 
  • Pergolas/verandahs/awnings where they are the only thing being constructed. 


Visit the BASIX Website for the BASIX online tool for detached and single attached dwellings (with supporting help notes and design guidelines) and the draft legislation establishing BASIX.