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NatHERS Energy Efficiency Ratings

House energy rating through the Nationwide House Energy Rating Scheme (NatHERS) uses computer simulations to assess the potential thermal comfort of Australian homes on a scale of zero to 10 stars. The more stars, the less likely the occupants need cooling or heating to stay comfortable.

What is rated?

A dwelling can be rated before or after it is built. The rating depends on:

  • the layout of the home

  • the construction of its roof, walls, windows and floor

  • the orientation of windows and shading to the sun's path and local breezes

  • how well these suit the local climate.

Installing wall insulation
Visit for information about energy efficient design

Energy consumption by hot water systems, lights or household appliances is not part of the rating because those fittings are usually replaced several times during the life of the building.

What the stars mean

  • Zero stars means the building shell does practically nothing to reduce the discomfort of hot or cold weather.

  • A 5 star rating indicates good, but not outstanding, thermal performance.

  • Occupants of a 10 star home are unlikely to need any artificial cooling or heating.

  • More about star ratings...

Typical ratings

Houses built in 1990 averaged about 1 star on the NatHERS scale. Before the introduction of national energy efficiency regulations for houses in 2003, less than one per cent of Australian houses achieved 5 stars.

Many well designed houses are now being built above 6 stars or more, and examples are available on the Your Home website at:


First Rate 5 is one of the leading residential thermal performance assessment software. It is used by the majority of industry to rate the energy efficiency compliance of residential dwellings for ACTPLA.

First Rate 5 also applies to the 6-star standard under the National Construction Code of Australia (NCC). The standard applies to all new homes and major renovations and extensions.

The software integrates the AccuRate calculation engine to generate the home rating and can be used to rate an existing design or as an interactive tool to optimise it for or beyond compliance.

First Rate 5is accredited with the NatHERS protocol for National regulatory compliance which is administered by the Commonwealth Department of Climate Change and Energy Efficiency. The software tool generates ratings based on the NatHERS 0-10 Star scale for homes. The rating is independent of the size and type of housing. This means that all new housing has the potential to achieve a good energy efficiency rating.


The Australian Government Department of the Environment, Water, Heritage and the Arts is responsible for the development and ongoing operation of the NatHERS scheme that includes First Rate 5.

However, the Commonwealth does not guarantee, and accepts no legal liability whatsoever arising from or connected to, the accuracy, reliability, currency or completeness of any material contained in this NatHERS scheme.

This energy rating report is not a substitute for independent professional advice and clients should obtain any appropriate professional advice relevant to their particular circumstances.

The material in this energy rating may include the views or recommendations of third parties, which do not necessarily reflect the views of the NatHERS administrator, or indicate its commitment to a particular course of action.

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