The Building Sustainability Index (BASIX) is a scheme introduced by the NSW government in 2007 to regulate the energy efficiency of residential buildings. The BASIX provides an assessment rating of a residential development in terms of water efficiency, thermal comfort and energy usage. 

The Building Sustainability Index is designed to achieve a 40% reduction in both water consumption and greenhouse gas emissions and is implemented under the Environmental Planning and Assessment Act 1979. It is an integrated part of the planning system that applies to all residential dwelling types and is an integral part of the development application process in NSW.



BASIX delivers equitable, effective water and greenhouse gas reductions making it one of the strongest sustainable planning measures to be undertaken in Australia.

BASIX aims to reduce water and energy consumption in homes providing long term financial savings for the homeowner – and a valuable contribution to the sustainable future of our communities.

Energy Efficiency is the goal to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature.

Installing LED lighting, fluorescent lighting or natural skylight windows reduces the amount of energy required to attain the same level of illumination compared to using traditional incandescent light bulbs.

Reducing Energy use is also seen as a solution to the problem of reducing greenhouse gas emissions. According to the International Energy Agency (link to, improved energy efficiency in buildings, industrial processes and transportation could reduce the world's energy needs in 2050 by one third, and help control global emissions of greenhouse gases. And the best part about that is that we can all do our bit to assist with this process!


If you are developing and constructing any of the following, then the answer is “Yes”.

  • Single Dwelling

  • Multi Dwelling

  • Secondary Dwelling

  • Swimming Pool with a volume greater than 40,000 Litres

  • Alteration or Addition valued at $50,000 or more

Stellar Thermal Assessments are Accredited Thermal Performance Assessors with HERA (House Energy Rating Association), Accreditation Number HERA10004. We will thoroughly assess your plans and recommend the most efficient methods in achieving compliance and guaranteeing a BASIX Certificate is issued.

Email us and send through your plans and we will respond within 24 hours with a fee proposal.

Please specify your preferred turnaround time as per below and we will provide the draft report as required.

  • 3 business days

  • 5 business days; or

  • 10 business days

what we require from you…

Contact us for a fast, no obligation free Quote today

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