What is Basix? - Owner Builder Club

What is Basix?

What is BASIX?

What is Basix you ask? Well, we found it to be a pretty in-depth topic but we'll do our best to make it as easy as possible to understand so let's dive in and learn more!


In an effort to regulate the energy efficiency of residential buildings, the government of New South Wales (NSW), Australia, introduced the Building Sustainability Index (BASIX) way back in July 2004.

The initiative was designed to reduce household water and electricity consumption in NSW by 40% and is measured by way of targets.

The use of the term BASIX is therefore only used in NSW. We'll go into what it means in other states further down this article.


One of the fundamental aspects of BASIX is the sustainability targets it sets for water and electricity. These targets outline minimum performance levels for residential buildings.

The targets are a percentage saving against the NSW benchmark. They are adjusted to accommodate regional climates and various housing types.

Is Basix Compulsory?

Yes, Basix is compulsory for all residential buildings and is part of the development application process. It needs to be done BEFORE submitting plans to Council.

How is it Assessed?

The NSW Government offers a BASIX online assessment tool. The website itself is pretty basic and quite comprehensive – click here to head to the site where you'll find a great deal of information. 


Upon meeting the BASIX target requirements and paying a $50.00 fee, a BASIX certificate is issued. This certificate is a mandatory attachment to all development plans in NSW. It serves as proof to a building's adherence to the energy efficiency standards outlined by BASIX.


For a development plan in NSW to be approved by your Council, it must have a BASIX Certificate attached.

Who can Help with BASIX?

It's not been easy to find the type of professional that can assist with BASIX however we didn't give up!

We came across Certified Energy, a team of assessors and consultants that provide a range of services. They have a ‘Quote Now' option on their site so worth checking out!

What Does BASIX Mean in Other Australian States?

What is BASIX in AustraliaAlthough every state and territory must comply with the National Construction Code (NCC) requirements, there are certain state and territory exemptions and dispensations.

As a result, the application of BASIX-like regulations can vary from state to state.

Unfortunately, search results do not offer detailed information about the exact BASIX requirements in other states and territories of Australia. However, it's important to note that each state or territory may have its building sustainability measures. Here’s what we came up with.

Victoria (VIC)

In Victoria, building sustainability and energy efficiency are measured through the Build Environment Sustainability Scorecard (BESS) assessment. The BESS assessment evaluates the thermal comfort, water efficiency, and energy efficiency of residential buildings. It ensures that new developments comply with the state's environmental and sustainability standards.

The assessment is designed to help reduce the environmental impact of buildings and promote energy efficiency. Similar to the Building Sustainability Index (BASIX) in New South Wales, BESS aims to regulate and improve the sustainability of buildings in Victoria.

Queensland (QLD)

In Queensland, the energy efficiency of houses is measured using a 6-star energy equivalence rating, which is determined by the design of the building's shell, including its roof, walls, windows, and floors.

This rating is regulated through the Queensland Development Code 4.1—Sustainable Buildings.

Optional credits for outdoor living areas and photovoltaic solar energy systems can contribute to meeting the 6-star minimum standard. However, a house cannot be promoted as having more than 6 stars if those additional stars rely on optional credits.

A new 7-star energy standard for houses will apply from May 1, 2024. Until then, new houses must achieve a minimum 6-star energy equivalence rating.

The 6-star standard is part of the Nationwide House Energy Rating Scheme (NatHERS) and aims to make buildings more energy-efficient and comfortable while minimising energy use for artificial cooling and heating.

Western Australia (WA)

In Western Australia, energy efficiency in residential buildings is regulated by the Building Code of Australia (BCA), which sets minimum standards of efficiency relevant to the climate zone, including building fabric, glazing, insulation, sealing of the building, air movement, services, electricity, and water use.

The Energy Efficiency of Residential Buildings Regulations 2019 (Regulations) also apply to the energy efficiency of buildings in Western Australia.

Sustainability WA is a program that offers accredited assessors to visit homes and conduct a thorough on-site assessment, collecting data covering construction materials, energy efficiency, and other factors.

The state government has been working on initiatives to improve energy efficiency in public buildings, such as the Health and Wellbeing Fund, which provides funding to improve energy efficiency and reduce greenhouse gas emissions in public buildings.

South Australia (SA)

In South Australia, sustainability and efficiency regulations for buildings aim to reduce greenhouse gas emissions, improve energy efficiency, and promote sustainable development. They apply to both residential and commercial buildings.

Energy efficiency assessments are a significant part of these regulations. These assessments determine compliance with the energy efficiency requirements outlined in the National Construction Code (NCC).

All new homes or extensions built in South Australia must meet these minimum energy efficiency requirements.

In addition, the South Australian Government has recently introduced new building requirements to enhance energy efficiency. From 1 October 2024, all newly constructed homes in the state will be required to meet higher minimum requirements for energy efficiency.

Tasmania (TAS)

For residential buildings, Tasmania requires a minimum 6-star energy efficiency rating for new homes and extensions.

Like Queensland, this rating is generated by an accredited NatHERS assessor using licensed software, which indicates a dwelling's efficiency in preserving energy.

The energy rating data is organised by Australian states and territories, including Tasmania, and is used to measure the energy efficiency of buildings. 

Australian Capital Territory (ACT)

The Australian Capital Territory (ACT) has implemented a mandatory Energy Efficiency Rating (EER) system.

This system evaluates the energy efficiency of a building's design, construction, and appliances. In addition, there's the Nationwide House Energy Rating Scheme (NatHERS), which assesses a building's thermal performance and rates it from 0 to 10.

When applying for building approval in the ACT, it's necessary to demonstrate the EER. The building certifier will need evidence that the building meets the mandatory minimum energy efficiency standards before granting approval.

In the ACT, a minimum energy efficiency rating of four stars is mandatory. This standard was established to raise awareness among the community and the building industry about the advantages of energy-efficient design.

To demonstrate the EER, one can use a current accredited software model. This process should be performed by a trained and competent accredited energy assessor or by contrasting the building with a reference.

Northern Territory (NT)

In the Northern Territory, specific energy efficiency standards and rules apply when building or modifying a home and a building permit is required. All new houses and renovations must achieve a 5-star energy rating, while all new apartments must meet a 3.5-star energy rating.

These star ratings are determined under the Nationwide House Energy Rating Scheme (NatHERS). Accredited energy assessors calculate these ratings, and they can issue a NatHERS certificate. A higher star rating signifies a more energy-efficient property.

Starting October 1, 2023, all new homes in the Northern Territory will require a NatHERS certificate.

It's worth noting that the Northern Territory has chosen not to adopt the changes to the National Construction Code (NCC). Instead, it will continue to build new houses with 5-star energy efficiency ratings under the Building Code of Australia 2009.

However, the Department of Infrastructure, Planning, and Logistics has incorporated energy efficiency requirements within all core building Minimum Design Standards for different construction types in the Northern Territory.


BASIX and the broader drive towards sustainability and energy efficiency in Australian homes represent a significant step forward. These initiatives are not only transforming our built environment but are also reshaping our understanding of what it means to live sustainably.

Through smarter design, innovative technologies, and a commitment to reducing our environmental impact, we are building a future where homes work in harmony with nature rather than against it.

This is an exciting time for homeowners and builders as we collectively strive to create a greener, more sustainable Australia.

Frequently Asked Questions 

Who can help me understand state based energy requirements?

We came across Certified Energy, a team of assessors and consultants that provide a range of services including NatHERS, BASIX and BESS. They have a ‘Quote Now' option on their site so they're highly worth checking out if you're in need of help!

What is the difference between passive and active design in homes?

Passive design uses natural sources of heating and cooling, such as the sun and wind, to maintain a comfortable temperature in the home. Active design involves using mechanical systems for heating, cooling, and ventilation, such as air conditioning or heating systems.

How can I improve the energy efficiency of my existing home?

Some strategies include improving insulation, installing energy-efficient appliances, using LED lighting, and implementing water-saving measures. Regular maintenance of heating and cooling systems can also enhance energy efficiency.

What are renewable energy sources for homes?

Common renewable energy sources for homes include solar panels, wind turbines, and geothermal energy systems. These systems can provide electricity for your home, reducing reliance on traditional, non-renewable energy sources.

What is a zero-energy home?

A zero-energy home is designed to produce as much energy as it consumes over the course of a year, typically through a combination of energy efficiency measures and on-site renewable energy generation.

What is a Green Star rating?

Green Star is a voluntary sustainability rating system for buildings and communities in Australia. It measures the sustainability of projects at all stages of the built environment lifecycle and rates them on a scale of one to six stars.

What is the EPC (Energy Performance Certificate)?

The EPC rates how energy-efficient your building is using grades from A to G (with ‘A' being the most efficient grade). It also provides suggestions for improving your home's energy efficiency.

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