All building work must comply with the New Zealand Building Code, whether it needs a consent or not. Unless a specific exemption applies, new construction work including additions or major remodelling is likely to require a building consent.
When is a consent not required?
Details of building consent exemptions can be found in the Building Act 2004 in section 41, Schedule 1 and Schedule 1A. The full text is available at www.legislation.govt.nz.
When carrying out repair and renovation work, the following activities are exempt from requiring a building consent:
- Repair and maintenance using comparable materials, components or details in the same position provided that:
» there has been no failure due to lack of durability or weathertightness performance within the specified minimum durability period required by the Building Code
» the replacement does not relate to elements installed to meet structural or fire safety requirements. - Repair or replacement of any open vented water storage heater with a comparable unit using the same pipework.
- Minor alteration to drains, for example, shifting a gully trap.
- Minor alteration to existing sanitary plumbing (for example, replacing a bath with a shower or moving a toilet).
- Installation, replacement or removal of a window (including a roof window) or an exterior doorway, provided structural stability is unchanged and the replacement is not to address a weathertightness or durability failure within the specified minimum durability period required by the Building Code.
- Alteration to an entrance or an internal doorway of a dwelling to improve access for persons with disabilities, provided the structural stability is not reduced.
Consent is also not required for construction, alteration or removal of:
- an internal wall (including the construction, alteration or removal of an internal doorway) provided structural stability is not reduced and the wall is not masonry
- a pergola
- an awning on or attached to an existing building, on the ground or first-storey level of the building, that does not exceed 20m2 and does not overhang any area accessible by the public. (Can be up to 30m2 if design or construction carried out or supervised by a licensed building practitioner.)
- a porch or veranda on or attached to an existing building on the ground or first-storey level of the building and that does not exceed 20m2 and does not overhang any area accessible by the public. (Can be up to 30m2 if design or construction carried out or supervised by a licensed building practitioner.)
- a deck, platform, bridge, boardwalk, or the like from which it is not possible to fall more than 1.5 metres even if it collapses.
- any retaining wall that retains not more than 1.5m depth of ground and that does not support any additional load other than the supported ground
- a fence or hoarding (except those restricting access to a residential pool) not exceeding 2.5 metres in height above the supporting ground.
All plumbing, drainage and gasfitting work whether consented or not, must be carried out in accordance with the Plumbers, Gasfitters and Drainlayers Act 1976.
Exemptions for constructing buildings
There are also building consent exemptions for complete small single-storey detached buildings and small stand-alone dwellings:
- The ‘single-storey detached building’ exemption is found in Schedule 1 of the Building Act. This refers to garden sheds, sleepouts and so on up to a maximum 30m2. The key features with sleepouts include that they can only be built when there is a principal residence on the site and they cannot include bathroom or kitchen facilities.
- The small dwellings building consent exemption is found in Schedule 1A of the Building Act. While the term ‘small stand-alone dwellings’ is what appears in the law, MBIE uses the phrase “granny flats” in a lot of its guidance material. These are self-contained homes up to 70m2. The Building Act exemption doesn’t require a principal residence to be on the same site.
There are significant conditions that apply to these consent exemptions. You can find more information in BRANZ bulletins BU703 Sleepouts exempt from building consent and BU704 Small dwellings exempt from consents.
Examples of consent-exempt work
If work is simply maintenance, such as repainting or replacing a damaged element such as a rotted weatherboard or window, a building consent is not required.
For repair work such as reroofing or recladding where the original cladding has met the durability requirements of the Building Code but ceased to be a serviceable cladding, as long as a comparable type of cladding is being installed, a building consent is not required. If, however, the recladding is being carried out because of a failure to meet Building Code performance such as weathertightness or durability, a building consent is required for the work.
When recladding a building, the reclad wall must have a thermal performance no less than that existing before the recladding was undertaken. However, when replacing the cladding, it is likely that the wall underlay will also need to be replaced, and this is a good opportunity (if the wall is not insulated or insulated to lower levels than currently required) to improve the performance of the building. Note that retrofitting wall insulation requires a building consent.
Prudent to get a building consent anyway
While a building consent may not be required, BRANZ considers it prudent to obtain one when alterations to layout and plumbing are being done. The reasons for this are that plans for the work need to be drawn up so that the work will be planned, there is a paper trail on the legality of the work through the consent process and the work will be inspected by the Building Consent Authority and, if correctly done, a Code Compliance Certificate will be issued on completion.
The drawback is that there is a time and a cost component, but this may pale into insignificance if a sale falls through as a result of the work carried out on the house not being deemed legal or adequate.