Find out your home energy rating in 2 minutes. Answer a few quick questions about your house and get an instant NatHERS-style star rating estimate (0–10 stars) — no signup, completely free, works anywhere in Australia. Not sure about a detail? Pick "Not sure" and we'll use typical values.
A home energy rating measures how energy-efficient your house is on a scale from 0 to 10 stars. The higher the star rating, the less energy your home needs to stay comfortable in summer and winter — meaning lower power bills and a smaller carbon footprint. In Australia, official ratings are issued under the NatHERS (Nationwide House Energy Rating Scheme), administered by the CSIRO and state governments.
You have two options. For an instant estimate, use the free home energy rating calculator below — it takes about two minutes and gives you a star rating plus tailored upgrade tips. For an official certificate (required when selling or renovating in many states), you'll need an accredited NatHERS assessor.
New builds in Australia must achieve at least 7 stars under NCC 2022. Most existing homes built before 2010 sit between 1.5 and 3 stars. Anything above 6 stars is considered efficient; 8+ stars is excellent.
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This calculator provides a rough estimate based on general building characteristics. An official NatHERS rating considers many more factors including exact construction details, orientation, shading, and thermal bridging.
New homes in Australia typically need a minimum 6-star rating. Homes rated 7+ stars are considered highly efficient, while 8+ stars represent excellent thermal performance.
Official ratings are required for new builds and major renovations in most Australian states. For existing homes, ratings are useful when selling, renting, or planning energy upgrades.