NCC 2022 Section J3.5 Airtightness Requirements Explained
A complete breakdown of the NCC 2022 airtightness requirements for Class 2 residential buildings — who it applies to, targets, testing methods, and compliance pathways.
Standards Reference
NCC 2022 J3.5
View Standard ↗
AS 9972:2015
ATTMA Technical Standard L2
Overview
NCC 2022 introduced mandatory airtightness testing requirements for Class 2 (multi-residential) buildings in Australia under Section J3.5.
Who Does It Apply To?
All new Class 2 residential buildings with a building permit date on or after 1 May 2023 in Climate Zones 6, 7, and 8. From 1 October 2023 it applies nationally.
The Target
Buildings must achieve ≤ 10 m³/(h·m²) at 50 Pa for the whole building. Statistical sampling is permitted for large multi-residential developments.
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