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
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: www.yourhome.gov.au