NCC2025 and Residential Energy Efficiency

We would like to provide an update on the implementation of the National Construction Code (NCC) 2025 and outline what it means for the energy efficiency assessment of residential buildings in Western Australia.

Key Information

• NCC 2025 came into effect on 1 May 2026.
• Western Australia has a 12-month transitional period, allowing most residential applications lodged before 30 April 2027 to continue to be assessed under the previous code.
• For applications including private swimming pools, compliance with NCC 2025 has been mandatory since 1 May 2026, regardless of the transitional arrangements.
• Alterations and additions may continue to be assessed under NCC 2019 (including the WA Alterations and Additions protocol).
• While the WA transitional period allows eligible applications to be assessed under NCC 2022, some councils may require compliance with NCC 2025. We recommend confirming individual requirements with your local council.

Residential Changes 

For most residential projects, the changes introduced in NCC 2025 to Part H6 Energy Efficiency are minimal. The primary change affecting energy efficiency assessments is an update to the Elemental Provisions (Deemed-to-Satisfy) for external walls in Climate Zones 4–8.

A new provision has been introduced within the Elemental Provisions for external walls, providing greater flexibility for designs incorporating extended roof overhangs.

Under NCC 2022, roof overhangs exceeding the maximum values prescribed in the tables were not permitted within the Elemental Provisions, often preventing certain designs from being assessed using this pathway. NCC 2025 now permits extended overhangs, provided they cover no more than 15% of the total opaque external wall area of the dwelling (excluding windows and doors).

This additional provision has no impact on assessments made using the NatHERS/7-Star pathway.

Looking Ahead

The Australian Building Codes Board has also advised that no further residential changes (other than essential quality and safety measures) are planned until mid-2029, providing greater certainty and stability for the residential construction industry.

EV charging requirements have not been introduced for residential buildings at this stage, recognising that commercial provisions were already included in NCC 2022.

Can we help?

If you have any questions about how these changes may affect your projects or upcoming applications, please don’t hesitate to contact our team.

Learn more about NCC2025 and its impacts: NCC2025: A Guide for Busy Professionals

Learn more about EcoForm’s residential energy efficiency services: Residential Energy Efficiency
Want to calculate your predicted home energy rating? Use our free NatHERS calculator tool: Free NatHERS Energy Rating Calculator