Achieving a 7-star energy rating on a new home with exterior cladding

No matter where you live in Australia, an energy-efficient home is a priority, and recent government initiatives have made that law; changes to the NCC 2022 (National Construction Code) requiring that new homes reach 7-stars are now mandatory in Victoria, Queensland and in New South Wales.  While it means the expense to build a home increases, the savings and efficiencies created from a more sustainable home tend to offset this in the long term. In this article, we’ll cover:

• What elements contribute to a 7-star energy rating

• Break down the common terminology

• Explain how to communicate them to your builder

What contributes towards a 7-star energy rating?

There are lots of factors in achieving this high energy rating, and we’re sharing each with a brief explanation, in order of importance.

How can my material choice assist me in achieving a 7-star rating?

Hardie™ exterior cladding used on energy-efficient designs can help you reduce the build costs of a 7-star home, whilst also expanding your design possibilities. Hardie™ exterior cladding can be used as a full exterior solution for modern and energy efficient home designs - but remember, each design will be assessed on its merits by an energy efficiency assessor.

Hardie™ exterior cladding is a full exterior solution that can be used on both the ground and upper floor to help you to achieve a 7-star rating at a lower cost compared to brick veneer, whilst also expanding your design possibilities. Explore the Hardie™ Architectural Collection.

Keyword glossary

• Energy efficiency: Using less energy to achieve the same outcome. A home’s energy efficiency is calculated by measuring the amount of energy that is used for temperature management.

• Star Rating: Star ratings are based on information about the home’s design, construction materials and the climate where it is being built, providing a ranking (between 1 and 10) about the home’s thermal performance.

• 7-star: The new 7-star standard is the minimum that new homes are required to be built to, rated out of 10. It measures the level of energy efficiency in a home.

• NatHERS Certificate: Valid in all of Australia except for NSW (see BASIX), new homes are rated out of 10 using the Nationwide House Energy Rating Scheme (NatHERS). To achieve a certificate, a minimum of 7 stars is required. The NatHERS Certificate allows builders, certifiers and regulatory authorities to confirm that the building has been built to the design on which the energy rating assessment is based.

• NCC Update 2022: The National Construction Code Update 2022 requires that new homes reach 7-stars, and is now mandatory in New South Wales and from May 2024 in Victoria and Queensland.

• Energy Efficiency Assessor: Accredited professionals whose role is to facilitate sustainable outcomes in design to improve the energy efficiency of commercial and residential buildings.

• Building Certifier: Independent public officials who issue a development certificate if all legislative requirements are met.

• BASIX: a sustainability assessment tool for residential buildings in New South Wales. It stands for Building Sustainability Index.

How do I talk to my builder about an energy efficient home upgrade?

Using less energy doesn’t have to be costly or complicated. For an accredited assessor to assess a project through the NatHERS process, they require the full plans, sections and elevations for the building as well as the building materials and glazing types that are intending to be used. So your builder should be on board with the desired outcome from the beginning.

Good communication is essential when working with a builder - read our tips for maintaining a great relationship here.

Share the MyHardies platform with your builder to help them access useful information to build and design your new home to a 7-star energy rating.