Front view of a modern house

What is NatHERS?

Fact Checked Fact Checked

In this guide, Canstar Blue breaks down the NatHERS process for you, from how to find an assessor to the expected costs.  

If you’re in the middle of a new build, then you’re probably not too fussed about getting a sustainability and energy efficiency rating for your home. But it may just be one of the most important jobs on your to-do list, especially with most states and territories having a required minimum for safety, health and sustainability in home designs.

NatHERS is one of the most common rating systems used in Australia for home energy efficiency, but just what is it exactly? And how do you obtain a NatHERS rating? We explain all below.

What is NatHERS?

Introduced in 1993, the Nationwide House Energy Rating Scheme (NatHERS) is used to measure the energy efficiency of a home and appoint it with a star rating. This scheme was implemented by the Australian Government to help uphold design standards and make homes more energy efficient. In its current state, the NatHERS scheme supports the residential energy efficiency standards outlined in The National Construction Code 2022.

The NatHERS rating of a home will rely on a number of factors including the building materials and methods used, size of rooms, the layout and orientation of the dwelling and whether the home is in a position to utilise shading or breezes. It has also been recently updated to included information regarding the greenhouse gas emissions of a home, the costs and energy used by major appliances and the impact of solar and batteries. This update now sees the rating broken into two parts – a NatHERS rating, which measures the thermal star rating of a home out of 10 and the Whole of House rating, which measures the energy usage of the home appliances on a scale out of 100.

Advertisement

What is a NatHERS Assessor?

Person holding checklist in a blue shirt

A NatHERS Assessor is an organisation that is trained, certified and accredited to perform the NatHERS thermal assessment software and award an efficiency star rating under the national Assessor Accredited Organisation (AAO). There are three organisations which train companies under the AAO; the Australian Building Sustainability Organisation (ABSA), Design Matters National and House Energy Rates Association (HERA).

To find a NatHERS Assessor, you or your builder will need to contact one of the above organisations in order to be directed to one in your local area.

Is NatHERS compulsory?

While NatHERS itself isn’t a compulsory rating, there are minimum necessary requirements around the safety, health and sustainability of new building designs and constructions under The National Construction Code which, a NatHERS rating can help to measure. Some states and territories may have other certification systems to determine these rating features but NatHERS is the most common system for an accreditation in health, safety and sustainability in Australia. According to the government’s NatHERS website, about 90% of new home designs in Australia are assessed using NatHERS.

Compare cheap electricity plans

Here are some of the cheapest published deals from the retailers on our database that include a link to the retailer’s website for further details. These are products from referral partners†. These costs are based on the Ausgrid network in Sydney but prices may vary depending on your circumstances. This comparison assumes general energy usage of 3911kWh/year for a residential customer on a single rate tariff. Please use our comparison tool for a specific comparison in your area. Our database may not cover all deals in your area. As always, check all details of any plan directly with the retailer before making a purchase decision.

Here are some of the cheapest published deals from the retailers on our database that include a link to the retailer’s website for further details. These are products from referral partners†. These costs are based on the Citipower network in Melbourne but prices may vary depending on your circumstances. This comparison assumes general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Please use our comparison tool for a specific comparison in your area. Our database may not cover all deals in your area. As always, check all details of any plan directly with the retailer before making a purchase decision.

Here are some of the cheapest published deals from the retailers on our database that include a link to the retailer’s website for further details. These are products from referral partners†. These costs are based on the Energex network in Brisbane but prices may vary depending on your circumstances. This comparison assumes general energy usage of 4613kWh/year for a residential customer on a single rate tariff. Please use our comparison tool for a specific comparison in your area. Our database may not cover all deals in your area. As always, check all details of any plan directly with the retailer before making a purchase decision.

Here are some of the cheapest published deals from the retailers on our database that include a link to the retailer’s website for further details. These are products from referral partners†. These costs are based on the SA Power network in Adelaide but prices may vary depending on your circumstances. This comparison assumes general energy usage of 4011kWh/year for a residential customer on a single rate tariff. Please use our comparison tool for a specific comparison in your area. Our database may not cover all deals in your area. As always, check all details of any plan directly with the retailer before making a purchase decision.

What is a good NatHERS rating?

NatHERS uses a 10-point star system when rating your dwelling. On this scale, the higher the number, the more ‘thermally comfortable’ a home is, meaning less energy is needed to heat and cool the property. Seven stars is the current minimum rating acceptable for a new house, while new apartment buildings will need an average rating of seven stars across all its apartments, with no single apartment scored under six stars. New homes will also need a Whole of Home rating of at least 60 out of 100, with apartments requiring a minimum 50 out of 100 score. These minimum standards are reflective of the standards set in The National Construction Code 2022.

What is the difference between BASIX and NatHERS?

While NatHERS is a national home scheme that awards an overall energy rating, the Building Sustainability Index (BASIX) is a New South Wales Government initiative that looks closely at three specific areas of the home; water, thermal and energy. BASIX uses a simulation method to determine whether or not a house will meet the energy, water and thermal minimum sustainability targets in NSW. Like with NatHERS, a BASIX certificate is required when lodging an application for development in NSW. A NatHERS energy rating can be used to determine the target heating and cooling performance of a home under the BASIX certificate though.

How much does a NatHERS star rating and certificate cost?

The cost of a NatHERS star rating and certificate will vary depending on the size and design of your home. That being said, you can expect to be out of pocket at least a few hundred dollars for an assessment.

How to make your home more energy efficient

If you are currently designing your new build and looking to make it a little more energy efficient, there are a few minimal to no extra cost changes you can implement to ensure your home has a sufficient rating. Things like adequate ventilation and air movement, proper insulation, window glazing and efficient lighting designs can all assist in making your home more thermally protected and efficient.

There are also plenty of ways you can make your home more energy efficient through the interior too. Switching your lightbulbs to LED and choosing appliances for your home that have a high energy efficient rating are simple ways you can ensure your house is as efficient as it can be, not only helping the environment, but potentially your wallet too.

If you’re moving into a new build or simply looking to save a few dollars, it may also be worth taking the time to compare energy providers in your area. Our free comparison tool lets you compare a wide range of retailers against a variety of criteria. Just click on the banner below, type in your postcode and you will be good to go.


Image credit: Image Supply/Shutterstock.com, GBJSTOCK/Shutterstock.com.

Kelseigh Wrigley
Energy Specialist
Kelseigh Wrigley was a content producer at Canstar Blue for three years until 2024, most recently as an Energy Specialist. She holds a Bachelor of Journalism from the Queensland University of Technology.

Share this article