What is BASIX

The Building Sustainability Index (BASIX), is a NSW Government planning measure to reduce household electricity and water use by setting minimum sustainability targets for new and renovated homes.

BASIX identifies design features that will affect the likely level of thermal comfort and water and energy use per household based on the location, building size, orientation, construction type, landscaping and fixtures. It sets minimum targets that must be achieved before a BASIX Certificate can be generated, and then submitted as part of a Development Application or Complying Development Application.

What Developments require a BASIX Certificate

BASIX applies to:

  • All new residential dwellings,
  • Alterations and additions to dwellings that cost $50,000 or more,
  • Swimming pools of 40,000 litres or more.


How do I obtain a BASIX Certificate

To demonstrate your development meets the BASIX requirements, you must conduct an assessment using the online BASIX Tool, which estimates the water and energy consumption and the thermal comfort based on the information you provide. This information includes the floor area, the size, location and type of windows, the type of insulation and the type of hot water system being installed.

There are detailed help notes available on the BASIX website to guide you through the process.

Once you have successfully completed the assessment by meeting the BASIX targets, you must generate the BASIX certificate and submit it with your Development Application or Complying Development Certificate


Related Information

BASIX Certificate

Assistance with the BASIX Tool