You have the plans, a growing list of decisions, and a few unfamiliar acronyms in your inbox. Understanding what each assessment does makes the next conversation with your designer or builder much easier.
What does NatHERS tell you?
The Nationwide House Energy Rating Scheme uses a rating out of 10 stars to describe modelled thermal performance: the heating and cooling a home is estimated to need. The assessment considers the building design in its local climate.
A thermal rating and a Whole of Home assessment describe different things. Whole of Home considers household energy use, including systems and appliances, alongside thermal performance. Ask your assessor which assessments your project needs.
Where does BASIX fit?
BASIX is a NSW assessment framework covering water, energy use and thermal performance. A NatHERS thermal assessment may contribute to the thermal performance component; the two names should not be treated as interchangeable certificates.
The right pathway depends on the location, project type and applicable requirements. Before ordering an assessment, share your plans and approval stage so the scope can be confirmed.
Three useful questions to ask
You don't need to arrive with all the answers. Start with a clear description of the project and ask:
- Which assessment and documentation does this project need?
- Which specifications need to be confirmed before modelling?
- What happens if the drawings or product selections change?
Bring the assessment into the design conversation
Think of an assessment as an opportunity to understand your design. Ask your team to explain the result in terms of the choices you are making, and keep the final documentation together with the drawings it relates to.
Sources & further reading
Explore the official guidance behind the technical topics in this article. Project requirements should be confirmed for your location and proposal.
