Building consent exemption conditions for granny flats

The building consent exemption for granny flats will commence in early 2026, following the passage of the Building and Construction (Small Stand-alone Dwellings) Amendment Bill and supporting regulations.

Building and Construction (Small Stand-alone Dwellings) Amendment Bill — legislation.govt.nz

This checklist explains the conditions that you will need to meet to build a granny flat without a building consent.

Granny flat design conditions and requirements for the building consent exemption

To build a granny flat without requiring a building consent, the building must follow a simple design that meets these proposed design conditions.

The building must comply fully with all the relevant requirements of the New Zealand Building Code to be able to use the building consent exemption.

Single storey, standalone and be self-contained

• ⁠The building must be new and standalone.
• The building must be single storey and cannot include a mezzanine floor.
• The building may include an internal garage.
• The building is classified as: Housing – detached dwelling (defined by Clause A1 of the Building Code). This means it must:
  • comply with all the requirements of the Building Code that apply to this classified use
  • be intended for a single household or family.

Check building classified uses in Clause A1

Building dimensions

• The net floor area must be 70 square metres or less. Floor area means the overall internal dimensions measured between the finished internal faces of the external walls.
• The building must have:
  • a maximum floor level of 1 metre above the supporting ground (measured from the lowest point of elevation)
  • a maximum height of 4 metres above the floor level.
• The building must be 2 metres or more away from any other residential building or legal boundary.
• The building cannot be built across boundaries between allotments.

Construction material

• The building's roof must be designed and built using lightweight building products for the roof with a maximum weight of 20 kilograms per square metre.
• The frame must be built using light steel or light timber.
• Wall cladding must have a weight not exceeding 220 kilograms per square metre.

Amenities

• Plumbing and drainage systems must connect to network utility operator (NUO) systems where available.
• Where no NUO system exists, or the NUO confirms insufficient capacity to connect, onsite water systems can be used. These can be existing onsite systems or new onsite systems, both of which can be modified or built without a building consent.
• Sanitary plumbing and drain laying for consent-exempt granny flats must be designed and built in accordance with the following acceptable solutions for compliance with clauses E1, G12, and G13 of the Building Code:
  • E1/AS1, E1/AS2 or E1/VM1 for its surface water system G12/AS1 or G12/AS3 for its water supply system, and
  • both G13/AS1 and G13/AS2 or G13/AS3 for its foul water drainage system.
• They must also meet specific criteria: 
  • maximum 30 fixture units
  • no pumped systems inside the building
  • main drain ≥ DN100 at 1:60 grade
  • branch drains ≥ DN65 at 1:40 grade
  • upstream vents ≥ DN65
  • no uncontrolled water heating.
• Where NUO systems are not available, and the dwelling’s water supply, wastewater or stormwater systems are on-site systems, these systems must be designed and built in accordance with:
  • E1/AS1, E1/AS2 or E1/VM1 for its surface water system; and
  • G12/AS1 or G12/AS3 for its water supply system; and
  • G13/AS1, G13/AS2, G13/AS3 or G13/VM4 for its foul water drainage system.
• The building must have:
  • independent points of supply for electricity and gas (where applicable), and
  • electric or gas heaters, where heaters are installed.
• Level-entry showers will be permitted only once a relevant licence class has been established for Licensed Building Practitioners (LBPs).

Improving occupational licensing to help homeowners

How the Building Code works

Clause E1 Surface water

Clause G12 Water supplied 

Clause G13 Foul water

Licensed building professionals must supervise or carry out the work

• All work on a building must be carried out or supervised by licensed building professionals (LBPs and licensed plumbers, drainlayers, gasfitters and electrical workers).
• Upon completion of all building work, homeowners must collect and submit to the council a range of records and certificates that confirm the work was carried out by appropriately licensed building professionals and complies with the Building Code. These include:
  • Records of Work (RoW) from Licensed Building Practitioners (LBPs) who carried out or supervised restricted building work - LBPs are required to provide the Records of Work to both the homeowner and the council.
  • Certificates of Work (CoW) from designers for any restricted design work.
  • Energy work certificates, including electrical safety certificates and gas safety certificates (if applicable).
• Homeowners who intend to live in their consent-exempt granny flat will be able to wire certain parts of the dwelling themselves during construction using the domestic exemption (section 79 of the Electricity Act 1992). The work must be inspected by an electrical inspector.

Gas and electrical work, and energy work certificates

Councils must be notified

You must notify your council before you start to build and when building is complete.

Before building work starts

• Homeowners must notify their council of their intention to build using a new Project Information Memorandum (PIM) form. If the application is complete, the council must issue the PIM within 10 working days. The PIM enables councils to share relevant information with owners and supports the collection of development contributions.
• Where the construction of a dwelling occurs in a different location to the final location of the dwelling (for example, offsite manufacturing), a PIM is only required in relation to the final location.
• The PIM must be issued before any building work begins.
• Councils must advise homeowners on whether specific elements of the proposed building work are likely, unlikely or uncertain to meet the proposed building consent exemption. This is not an approval process and homeowners can choose to build irrespective of council advice.
• Councils must advise homeowners if the proposed building work is on land that is, or is likely to be, subject to one or more natural hazards, or if it unclear if a natural hazard is present. If there is, or is likely to be, a natural hazard present on the land, councils must also advise homeowners on:
  • whether the proposed building work adequately protects the land, building work or other property from the natural hazard (or will restore the land or other property resulting from the building work), or
  • whether they think that changes to the proposed building design or a building consent are required.
• Choosing to build on land where a natural hazard exists, as defined by section 71(3) of the Building Act 2004, may require a building consent. This is unless adequate provision has been made to protect the land, building work, or other property from the natural hazard.
• A homeowner will have two years to complete the build from the PIM issue date.
• If a PIM lapses and building work is not complete, homeowners will need to get a new PIM or talk to their council about extending the timeframe of the original PIM. This ensures that the information provided by a council is up to date and supports homes to be built to the Building Code.

When building work is complete

• Building work is considered complete once a homeowner has received all relevant records of work, certificates of work, certificates of compliance, electrical safety certificate and gas safety certificate from licensed building professionals.
• Homeowners must provide councils, within 20 working days on completion of work, a set of plans for both building and plumbing and drainage work, all relevant records of work, certificates of work, certificates of compliance, electrical safety certificate and gas safety certificate.
• Plans must show the final design plans (actual drawings/specifications used for construction). This is an administrative process. Councils cannot review built plans to determine if a granny flat complies with the Building Code.
• Homeowners that fail to provide relevant documentation to councils within 20 working days may be subject to a new infringement offence.
• Homeowners must pay any development contributions charged within 20 working days of completion of building work.
• Homeowners must meet all building consent exemption conditions. Otherwise, they are required to get a building consent.
• The granny flat building consent exemption is expected to commence in early 2026. Existing building work underway is not eligible to be exempt from requiring a building consent. Councils retain their existing powers to address non-compliant building work.

Find out more

The Government is making it easier to build granny flats, improving affordable housing options and ensuring Kiwis have safe, healthy and durable homes to live in.

Keep up to date with future changes to granny flat building consent rules