About BASIX  

Introduced by the NSW Government, BASIX, the Building Sustainability Index, ensures homes are designed to use less potable water and be responsible for fewer greenhouse gas emissions by setting energy and water reduction targets for house and units. BASIX is one of the most robust sustainable planning measures in Australia, delivering equitable and effective water and greenhouse gas reductions across NSW.

How does BASIX work?

BASIX is an online program that is free and accessible to anyone. The user (usually the building designer) enters data relating to the house or unit design - such as location, size, building materials etc - into the BASIX tool. BASIX analyses this data and determines how it scores against the Energy and Water targets. The design must pass specific targets (which vary according to location and building type) before the user can print the BASIX Certificate.

The BASIX Certificate

This lists all the commitments the user has agreed to, and the Certifying Authority will check these at various stages of construction. The BASIX Certificate must be attached to the development application before it can be processed. Click here to see a sample BASIX Certificate for a single home (pdf 68kb).

Providing options

BASIX is free, flexible and easy to use, allowing users to determine how they will meet targets from a wide range of options such as rainwater tanks, water-saving fixtures, improved insulation, passive solar orientation, natural lighting and native plants for gardens.

More information

BASIX Fact Sheet (pdf 54kb)
About the BASIX Indices (pdf 382kb)
BASIX for Alterations and Additions
What a BASIX home looks like (384kb)
What a BASIX multi-unit looks like (357kb)
Helpnotes and FAQs

BASIX Timeline

BASIX introduced BASIX applies to
1 July 04
  • New single dwellings and dual occupancy;
  • New boarding houses, guest houses, hostels, lodging-houses and backpacker accommodation under 300m2.


    • In Sydney local government areas except Blue Mountains, Hawkesbury and Wollondilly.
1 July 05
  • New single dwellings and dual occupancy;
  • New boarding houses, guest houses, hostels, lodging-houses and backpacker accommodation under 300m2.


    • throughout NSW
1 October 05
  • all new residential dwellings, including single dwellings, villas, townhouses and low-rise, mid-rise and high-rise developments in NSW.
1 July 06
  • BASIX energy target is increased to 40% reduction in greenhouse gas emissions
1 October 06
  • all residential alterations and additions throughout NSW, with a total cost of works $100,000 or more.
1 July 2007
  • All residential developments throughout NSW with a total estimated cost of works of $50,000 or more.
About BASIX