6 Star Assessment on Residential Extensions

In Australia, all home alterations and extensions need to comply with the Energy Efficiency Provisions by the National Construction Code.

If your home extension is greater than 25% of the original size, say from 100m2 to 130m2, making it 30% larger, then a 6 star assessment might be required for the entire home.

What does this mean?
You might be required to upgrade a portion of the existing home to meet current standards.

Are there exceptions?
Yes. Sometimes, certain elements of the home cannot be changed, like double brick walls that can’t be insulated, or the existing home is elevated on stumps and the gap is too small to add insulation where there wasn't any.

What should I do in these situations?
When it is not possible for the home to achieve a 6 star rating due to unchangeable conditions, a Seeking Dispensation Clause will need to be requested, to excuse those elements of the existing home, and for them to be left as is.

Partial Compliance for Residential Extensions

A different method to assess for a 6 star rating will need to be used if your home extension is under 25% of the original size, consisting of two separate reports.

One report needs to be produced for the original home, which will rate under 6 stars (houses built in 1990 averaged about 1 star on the NatHERS scale).

A second report for the new extension needs to achieve a 6 star rating. We will likely recommend upgrading a few key areas of the existing home to bring the whole home up to standard. These are often cost-effective and thermally efficient outcomes.