A national multiple-use approval (known as a multi-proof) is a statement by the Ministry of Business, Innovation and Employment (MBIE) that a set of plans and specifications for a building complies with the New Zealand Building Code.
Under the Building Act 2004, Building Consent Authorities (BCAs) must accept a current multi-proof as evidence of Building Code compliance if every relevant condition in that multi-proof is met. Multi-proofs allow builders who replicate the same or substantially similar buildings several times to benefit from a streamlined building consent process.
A multi-proof is not, and does not replace, a building consent. The holder of a multi-proof must obtain a building consent each time they wish to build the approved design. This enables the BCA to confirm and establish:
- the design, with any permitted variations, is the same as the one in the plans and specifications approved as part of the multi-proof
- the proposed site meets the conditions of the multi-proof conditions
- any site-specific features of the design comply with the Building Code
- the inspections required.
However, because the BCA only needs to assess the Building Code compliance of site-specific features excluded from the multi-proof, the statutory timeframe for the BCA to grant or refuse a building consent for applications that rely on a multi-proof is 10 working days instead of the usual 20.
Permitted variations
Permitted variations are design alternatives for a multi-proof. The permitted variations will be listed on the multi-proof, and a building consent authority can assess the plans and specifications included in the building consent application with the approved plans and specifications MBIE has on file.
Minor customisations
A 'minor customisation' is a change to the building design of a multi-proof approval at the time a building consent is applied for. A minor customisation could be putting a window where a door was planned in the initial design or mirroring the layout of a room to maximise sunlight or to work with a specific landscape. If a multi-proof holder would like to make a minor change to their multi-proof, they may do so at the building consent application stage.