Energy equivalence building standards (star and whole of home ratings)

Since 1 May 2024, the National Construction Code 2022 (NCC) Modern Homes residential energy efficiency standards have been required in Queensland, through amendment of the Queensland Development Code 4.1 – Sustainable Buildings (QDC 4.1).

The residential energy efficiency standards apply to new houses and new units, and require compliance with 2 key aspects:

• Energy equivalence rating (thermal performance) for the dwelling’s building shell (out of 10 stars)
• Whole of home score (out of 100) to assess the energy budget of the dwelling’s major fixtures and appliances, including any solar photovoltaic (PV) energy system.

QDC 4.1 includes variations and additional compliance pathways that support the practical application of these provisions in Queensland.

Energy equivalence rating

The energy star rating of a new house, townhouse or unit reflects the thermal performance of its building shell, including its roof, walls, windows and floors.

A more energy efficient building shell can improve comfort and reduce the energy needed for artificial heating and cooling. Thermal performance is expressed on a scale of up to 10 stars, with a higher rating indicating better performance.

Under Queensland's residential energy efficiency requirements, the dwelling's building shell must achieve:

• 7 stars for most houses and townhouses
• 5 stars for eligible small homes of 50 square metres or less under QDC 4.1
• 6 stars for eligible houses with raised floor construction under QDC 4.1.

QDC 4.1 also provides a Queensland-specific compliance pathway for houses in National Construction Code (NCC) climate zone 5 with a floor over an unenclosed space.

An optional credit of up to 1 star for a compliant outdoor living area may be used towards achieving the applicable minimum rating, including for an eligible small home or house with raised floor construction.

New multi-unit residential buildings (class 2) must also achieve an average 7-star energy equivalence rating for all units in the building, with no individual unit to be rated less than 6-stars. This accounts for the different orientations and elevations of the individual units within the building (e.g. units with a southern orientation have less solar access).

Whole of home score

Whole of home assessments aim to lower energy costs by helping homeowners make cost-effective choices about their home's major fixtures and appliances. Homeowners, designers and builders can explore the trade-offs and benefits of different technologies and appliance efficiencies that works for them and their budget.

The Whole of home score ranges from 0 to 100 – a poor energy performing home would rate under 40, while a score of 100 is a net zero energy home. A score over 100 is possible where the home is producing more energy than it uses i.e. where it includes a large solar PV system.

A new house needs to achieve a minimum Whole of home score of 60 (out of 100) and a new unit apartment needs to achieve at least 50 (out of 100).