J1V5 (NCC Section J verification method)
J1V5 is the NCC 2022 Section J verification method for Class 2 apartments, a reference-building path capping heating and cooling loads at 120% of the J1P2 thermal limits.
Ask Chalkline about this →J1V5 is a verification method in Section J (energy efficiency) of NCC 2022 Volume One, introduced in NCC 2022, for demonstrating the energy-efficiency compliance of individual Class 2 sole-occupancy units (SOUs), that is, apartments. It is a reference-building method: the proposed unit must show heating and cooling loads no greater than 120% of the J1P2 thermal load limits, or match the performance of a defined reference building. As a verification method it is an alternative to the elemental Deemed-to-Satisfy provisions, and it is effectively the Class 2 equivalent of the NatHERS pathway used for Class 1 homes.
J1V5 sits alongside J1V3, the reference-building method used for Class 2 common areas and for Class 3 and 5 to 9 buildings. In short: J1V3 handles the common areas, J1V5 handles the apartments themselves. Both verify against the Section J Performance Requirements rather than the prescriptive fabric provisions.
A New South Wales carve-out matters. In NSW, the Section J performance requirements J1P2 and J1P3 and the J1V5 method do not apply to Class 2 buildings up to 5 storeys, because BASIX covers those units instead. For Class 2 buildings above 5 storeys, Section J and J1V5 apply. Check the storey count and the state before assuming which energy pathway governs a project.
Also known as: J1V5 verification method, Section J Class 2 SOU verification.
Category: Energy efficiency / NCC Section J.
Related
See also
References
- NCC 2022 Volume One Part J1 Energy efficiency, ABCB (verified 2026-05-09)
- ABCB: NCC energy efficiency provisions (verified 2026-05-09)
Last updated: 2026-05-30. Verified: 2026-05-09. Quarterly review for currency.