Energy equivalence building standards (star and Whole of Home ratings)
On 1 May 2024, the National Construction Code 2022 (NCC) Modern Homes residential energy efficiency standards commenced through amendment of the Queensland Development Code 4.1 – Sustainable Buildings.
The new energy efficiency standards include a 7-star energy equivalence rating for houses and units and the introduction of a Whole of Home rating to measure the energy use of the home.
This guide explains how energy assessments are undertaken, how to achieve a 7-star energy rating and a high Whole of Home rating for new dwellings in Queensland.
7-Star energy equivalence rating
The 7-star energy equivalence rating of new houses, townhouses and units is determined by the design of the building's shell: its roof, walls, windows and floors.
Dwellings designed to be more energy efficient are more comfortable to live in, and can provide ongoing savings to householders by minimising energy use for artificial cooling and heating. Energy equivalence is expressed on a star rating scale, with 10 stars being the highest and most energy efficient.
New houses and townhouses (class 1 buildings) must achieve a minimum 6-star energy equivalence rating. 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.
Whole of Home rating
Whole of Home assessments aim to lower energy costs by helping homeowners make cost-effective choices about their home's appliances and equipment. Homeowners, designers and builders can explore the trade-offs and benefits of different technologies, appliance efficiencies and thermal performance to create a home and appliance design that works for them and their budget.
The Whole of Home rating scale ranges from 0 to 100 – a poor energy performing home would rate under 40, while a score of 100 is a net zero energy value home. A rating over 100 is possible where the home is producing more energy than it uses. Ratings at 100 or above mean the home will have low or no energy bills.
The new NCC 2022 residential energy efficiency standards mean new houses will need to meet a minimum Whole of Home rating of 60 (out of 100) and apartments will need to meet a minimum Whole of Home rating of 50 (out of 100).