NatHERS Foundations
NatHERS is one of Australia’s main frameworks for assessing the thermal performance of new homes and residential designs. It helps show how well a home is expected to stay comfortable in local climate conditions before it is built.
NatHERS stands for the Nationwide House Energy Rating Scheme. It provides thermal star ratings for Australian homes, commonly used for new residential design and compliance. A NatHERS rating considers design factors such as orientation, insulation, glazing, shading, construction materials and local climate to estimate how much heating and cooling a home may need to stay comfortable.
NatHERS is the national framework used to assess the thermal performance of Australian homes. In residential design and building approval, it is most commonly associated with the thermal star rating, which measures how well the building fabric is expected to perform in its specific climate.
The rating does not simply look at whether a home has solar panels or efficient appliances. At its core, a NatHERS thermal rating looks at the home itself: the walls, roof, floors, windows, orientation, shading and construction details that influence how much heating and cooling the home may need.
This is why NatHERS is closely connected to comfort. A higher performing home is usually easier to keep comfortable through hot and cold periods because the building fabric is doing more of the work before mechanical heating or cooling is needed.
A NatHERS thermal star rating measures the predicted heating and cooling load of a home. In simple terms, it estimates how much energy may be needed to keep the home comfortable across the year, based on the design and the local climate zone.
The scale runs from 0 to 10 stars. A higher rating generally means the home should need less heating and cooling to remain comfortable. A lower rating means the home may be more exposed to heat loss, heat gain or poor thermal performance.
For new homes, NatHERS is often part of the broader residential compliance pathway alongside requirements such as BASIX, Whole of Home and the National Construction Code.
NatHERS matters because many comfort and energy outcomes are locked in during design. Window size, window placement, orientation, insulation levels, roof colour, floor construction and shading can all affect how the home performs once it is built.
When NatHERS is considered early, it can help the design team understand whether the home is likely to meet the required performance level and where improvements may be needed. This can reduce the risk of late design changes, especially where glazing, insulation or shading decisions affect compliance.
For homeowners and project teams, a NatHERS star rating can make thermal performance easier to understand. Instead of treating comfort as a vague design outcome, the rating provides a clearer indication of how the home is expected to respond to local weather conditions.
NatHERS is often discussed alongside other residential energy requirements, but it does not cover exactly the same thing as every other scheme.
NatHERS: focuses on thermal performance and the heating and cooling needs of the home.
BASIX: applies in NSW and includes broader sustainability requirements such as water, thermal performance and energy targets.
Whole of Home: considers the energy use of appliances, hot water, heating and cooling equipment, solar and batteries as part of the broader home energy picture.
Australian homes are assessed in relation to their climate. A design that performs well in a cooler southern climate may not perform the same way in a hot or humid region. This is why NatHERS uses climate data rather than treating all homes across Australia as if they experience the same conditions.
Good NatHERS outcomes are usually created through a combination of design decisions. Insulation may help reduce heat transfer. Glazing can support daylight and views, but may also increase heat gain or heat loss if it is not carefully specified. Shading can reduce unwanted summer heat while still allowing useful winter sun in the right climate and orientation.
This is why NatHERS should not be treated as a final paperwork step. The assessment is most useful when it informs design decisions before the project is too far advanced.
Certified Energy provides NatHERS assessments for Australian residential projects, including new homes, townhouses and multi residential developments. Our team reviews the project documentation, models the proposed design and helps identify practical pathways toward the required thermal performance outcome.
If your project also needs related residential compliance support, we can help connect the NatHERS assessment with the broader approval context, including BASIX, 7 Star Rating, 6 Star NatHERS and Whole of Home requirements.
For a broader overview, visit our NatHERS Knowledge Hub.
NatHERS stands for the Nationwide House Energy Rating Scheme. It is used to rate the thermal performance of Australian homes, with the thermal star rating focused on heating and cooling needs.
Is NatHERS the same as BASIX?No. NatHERS focuses on thermal performance and star ratings. BASIX is a NSW sustainability requirement that can include water, energy and thermal performance commitments. Many NSW residential projects involve both NatHERS modelling and BASIX compliance.
What is a good NatHERS rating?A good NatHERS rating depends on the project, climate zone and compliance requirement. In general, a higher star rating means the home is expected to need less heating and cooling to remain comfortable.
Does NatHERS include solar panels?The NatHERS thermal star rating focuses on the building fabric and heating and cooling needs. Solar panels, appliances, hot water and other systems are considered through Whole of Home requirements where applicable.
When should a NatHERS assessment be done?A NatHERS assessment is best considered before the design is finalised. Early review gives the project team more flexibility to adjust glazing, insulation, shading or other design features before they become difficult to change.