7 Star NatHERS Requirements

Benchmark Application

When Does the 7 Star NatHERS Benchmark Apply?

The 7 Star benchmark is relevant to many new residential projects assessed using NatHERS, but the requirement applying to a particular dwelling depends on its location, building classification, approval pathway and applicable regulatory provisions.

Under the NCC 2022 residential energy-efficiency provisions, the minimum thermal-performance requirement is generally equivalent to 7 Stars on the NatHERS scale. Where a new house uses a NatHERS-based compliance pathway, the dwelling will commonly need to achieve a minimum 7 Star thermal rating.

For apartment buildings assessed through NatHERS, the requirement is generally applied across the building rather than as a single identical target for every apartment. The apartments must commonly achieve an average rating of at least 7 Stars, with no individual apartment rated below 6 Stars.

The National Construction Code is adopted and administered by individual states and territories. Commencement dates, local variations, concessions and transitional arrangements can therefore affect whether the NCC 2022 benchmark applies to a particular approval or project stage.

A 7 Star NatHERS certificate is also not the only possible way to address residential energy-efficiency requirements. The appropriate pathway should be confirmed against the project location, dwelling type and approval requirements before the design is finalised.

A note for projects in New South Wales

New residential development in New South Wales is also subject to BASIX requirements. NatHERS modelling may support the thermal-performance component of a BASIX assessment, but the two should not be treated as interchangeable systems. See the BASIX service guide for the wider NSW submission pathway.

Design Factors

What Influences a 7 Star NatHERS Result?

A 7 Star result is rarely created by one product or specification alone. It usually depends on how the dwelling form, building fabric, glazing and climate-responsive design decisions work together.

NatHERS software models the dwelling as a complete thermal system. A design decision that improves performance in one room, orientation or season may have a different effect elsewhere in the home. The rating therefore reflects the combined performance of the documented design rather than a simple checklist of compliant materials.

The most appropriate design response also varies by climate. Solar access may be beneficial in a cooler climate but can increase cooling demand where summer heat gain is difficult to control. Glazing, shading, insulation, thermal mass and ventilation openings should therefore be considered in relation to the dwelling’s location, orientation and pattern of use.

Early modelling allows these relationships to be tested while the design remains flexible. Where assessment is delayed until documentation is nearly complete, the available improvements may be narrower, more expensive or more disruptive to the architectural intent.

Does 7 Star require double glazing?

Not necessarily. Double glazing can improve performance, but whether it is required depends on the climate, window area, orientation, shading and the performance of the wider dwelling fabric. A coordinated design response is usually more reliable than treating one product as a universal solution.

Design Improvement

How Can a Project Reach 7 Star?

Where an initial NatHERS model falls below the target, the result can often be improved through coordinated changes to the dwelling fabric rather than relying on one product or specification alone.

The most effective pathway begins by identifying which parts of the design are contributing most strongly to heating or cooling demand. This may involve particular orientations, large areas of exposed glazing, insufficient shading, gaps in the insulation strategy or rooms that perform differently from the dwelling as a whole.

Potential improvements should then be tested within the NatHERS model. Depending on the climate and design, this could include refining window size or performance, adjusting shading, improving insulation, reviewing construction systems or reconsidering how rooms and openings respond to solar exposure and natural ventilation.

The strongest solution is not always the option with the highest individual product specification. A more balanced design may achieve the required outcome through several modest changes that preserve daylight, views, amenity, construction practicality and the architectural intent.

Once an improvement pathway has been agreed, the drawings and schedules should be coordinated with the modelled assumptions. Changes made later to glazing, insulation, shading or construction details may affect the rating and can require the design to be reassessed.

Earlier modelling usually provides more design flexibility

Testing the 7 Star target during design development allows the project team to compare improvement options before key dimensions, window selections and construction systems are fixed. Later assessment may still identify a pathway, but the available changes can be narrower and more disruptive.

Related Residential Frameworks

How Does 7 Star Relate to Whole of Home and BASIX?

These requirements may appear together on a residential project, but they assess different parts of dwelling performance and should not be treated as interchangeable ratings or approval systems.

A 7 Star NatHERS rating relates specifically to the modelled thermal performance of the dwelling fabric. It indicates the expected heating and cooling demand associated with the documented building form, construction, glazing, insulation, shading and climate response.

A Whole of Home assessment extends beyond the thermal star rating to consider the expected energy use of major fixed systems and appliances, together with energy generated or stored onsite. A dwelling can therefore achieve its required thermal star rating while still requiring separate review of its broader Whole of Home outcome.

In New South Wales, BASIX provides the wider residential sustainability assessment and submission framework. Its requirements address water, energy and thermal performance, as well as specified project information relating to construction materials. NatHERS modelling may support the thermal-performance component where the relevant BASIX assessment pathway uses simulation, but a NatHERS certificate does not replace the BASIX submission.

One project may require more than one outcome

Reaching 7 Star does not automatically demonstrate compliance with every residential energy or sustainability requirement. The complete project pathway should be confirmed by considering the thermal rating, Whole of Home requirements and any applicable state-based assessment framework.

Explore the Whole of Home guide or review the BASIX submission pathway.

Benchmark Transition

How Is 7 Star Different From the Former 6 Star Benchmark?

The move from 6 to 7 Stars increased the expected thermal-performance level for many new homes, but it does not translate into one fixed upgrade or a simple percentage improvement across every project.

Six stars was the minimum NatHERS benchmark associated with earlier residential energy-efficiency provisions. Under the NCC 2022 settings, the thermal-performance stringency for new homes increased to the equivalent of 7 Stars, subject to jurisdictional adoption and the compliance pathway applying to the project.

A 7 Star home will generally have lower modelled heating and cooling demand than a comparable 6 Star home assessed for the same climate. The scale is not linear, however, and the difference between the two ratings cannot be expressed as one universal percentage, energy saving or construction specification.

The design response required to move from 6 to 7 Stars also varies between projects. One dwelling may benefit most from better glazing or external shading, while another may require changes to orientation, insulation, thermal mass, ventilation openings or the relationship between rooms and solar exposure.

An existing 6 Star certificate should therefore be understood in the context of the approval date, applicable code and software settings under which it was produced. It does not automatically establish the target for a new project being assessed under current provisions.

Seven stars is not simply “one star better”

NatHERS star bands represent climate-specific limits on modelled heating and cooling demand. Moving from 6 to 7 Stars therefore requires a project-specific assessment rather than the automatic addition of one material, product or insulation level.

For more detail about certificates and projects assessed under the earlier benchmark, see the 6 Star NatHERS legacy guide.

Queensland Application

Can a Queensland Home Meet the 7 Star Standard With a Lower NatHERS Rating?

Queensland retains a state-specific energy-equivalence pathway that may allow a compliant outdoor living area to contribute towards the regulated 7 Star standard.

Under Queensland Development Code Mandatory Part 4.1, new houses and townhouses must achieve a minimum 7 Star energy-equivalence outcome. This can be demonstrated through a 7 Star building-shell rating or, where the relevant requirements are met, through a combination of a lower NatHERS rating and an approved outdoor living area credit.

For houses and townhouses, a compliant covered outdoor living area may provide a half-star credit. Where the outdoor area also includes qualifying ceiling fans, the available credit may increase to one star. The underlying building shell must still achieve at least 6 Stars.

These credits are used for regulatory energy equivalence only. They do not change the NatHERS rating shown on the dwelling’s certificate. A home with a 6 Star NatHERS certificate and a qualifying one-star outdoor living credit may satisfy the Queensland 7 Star standard, but it remains a 6 Star NatHERS-rated building shell.

For apartment developments, an outdoor living area credit may contribute to the required building-wide average. It cannot be used to reduce an individual apartment below the applicable 6 Star minimum, and the eligibility and calculation of credits should be confirmed for the particular project.

Energy equivalence is not the same as a 7 Star NatHERS certificate

The Queensland credit supports compliance with the state’s regulated 7 Star energy standard. It should not be added to the certified NatHERS rating or used to describe a 6 Star building shell as having achieved a 7 Star NatHERS rating.