Energy assessments for new dwellings

An energy assessment predicts how much energy would be required to cool and heat a dwelling to maintain its comfort over a year, based on the thermal performance of its building shell. It currently only deals with the thermal performance of the building, and does not include energy use from its fixtures and appliances (e.g. air conditioners and fridges).

However, this will change when new Modern Homes Whole of Home energy standards apply from 1 May 2024. The energy efficiency changes will for the first time, account for the energy usage of household appliances and equipment, and energy produced by on-site renewable energy (e.g. solar photovoltaic (PV) system). It has been more than a decade since the last change to the energy efficiency requirements for homes in the NCC.

The 2 most common energy assessment methods used for residential buildings (houses and units) are:

• software – using one of the software tools accredited under the Nationwide House Energy Rating Scheme (BERS Pro, AccuRate , HERO and FirstRate5), a house energy assessor predicts the design's thermal performance. The software generates a star rating between 0 to 10 stars – where a 10-star dwelling would require the least energy use for artificial cooling and heating. A NatHERS Certificate confirms the star rating of the building shell and provides a summary of the dwelling's energy efficiency features. More information on the software assessment method is available in Building and Plumbing Newsflash 548.
• deemed-to-satisfy (DTS) – using the more prescriptive provisions of the National Construction Code (through the Building Code of Australia—Volume Two).

Other energy assessment options are:

• peer review by an expert (read peer review guidelines)
• using a reference building by comparing to a design that is already known to comply.

Use of optional credits

In Queensland, a dwelling can use optional credits when it includes:

• a photovoltaic (PV) solar energy system (for houses and townhouses) – this option will cease on 30 April 2024, as solar PV systems are included in the Whole of Home assessment
• an outdoor living area (for houses, townhouses and units) – this option will be expanded on 1 May 2024 to apply state-wide in Queensland.

The optional credits can continue to be used towards achieving compliance for the dwelling's energy rating.

The 6-star housing and 5-star multi-unit residential building requirements are regulated through the Queensland Development Code 4.1—Sustainable buildings.

Also consider...

• Learn more about the Nationwide House Energy Rating Scheme (NatHERS).
• Learn more about energy assessments in Queensland (PDF, 422KB).
• Read the National Construction Code (NCC) for the construction of buildings.
• Read the Handbook for Energy Efficiency (NCC 2019, Volume Two).
• Read about passive design on the Australian Government's Your Home website.
• Learn more about Queensland's climate zones for dwellings and buildings.