New rules, in force 15 January 2026

Granny flat rules in NZ: what the 70m² exemption actually requires

Since 15 January 2026, a standalone, single-storey dwelling up to 70m² can be built without a building consent in New Zealand. The conditions most people miss: a PIM from the council is mandatory before you start, Licensed Building Practitioners must design and carry out or supervise the work, and the zone and any hazard or heritage overlays on the site decide whether the resource-consent side is also clear.

The two halves of the rule

Building consent side

  • Exemption in the Building Act (new section 42B, in force 15 Jan 2026).
  • Standalone, single-storey, up to 70m² floor area.
  • Designed, built or supervised by Licensed Building Practitioners.
  • PIM from the council is required before work starts, nationwide.
  • Notify the council before starting and after finishing.
  • The Building Code still applies in full. Exempt from consent, not from compliance.

Resource consent side

  • National standard (NES-DMRU) permits one minor residential unit per site.
  • Applies in residential, rural, mixed-use and Māori-purpose zones.
  • District plan setbacks, height and coverage standards still apply.
  • Sites with qualifying overlays (natural hazards, heritage and similar) are carved out: normal rules apply there.
  • Outside those zones, the district plan decides, as before.

Check the address first. The free property report shows the district plan zone and any hazard or heritage layers on the record for a specific address, which is exactly what decides how these rules land on your site.

Check an address

Common questions

Can I build a granny flat without consent in NZ?

Since 15 January 2026, yes, if it qualifies: a standalone, single-storey dwelling up to 70m² floor area, designed or supervised by Licensed Building Practitioners, on a site where the district plan or the national environmental standard permits it. You must obtain a Project Information Memorandum (PIM) from the council before you start and notify the council before and after the build. It is an exemption from building consent, not from the Building Code: the flat must still fully comply.

Do I still need anything from the council?

Yes. A PIM is mandatory nationwide before building under the exemption, and you must tell the council when you start and when you finish. The PIM is also where the council tells you about natural hazards, heritage listings and other constraints on the site that can take the exemption off the table.

Does the exemption apply in every zone?

No. The national environmental standard (NES-DMRU) makes one minor residential unit a permitted activity in residential, rural, mixed-use and Māori-purpose zones, subject to standards like one unit per site and the district plan's setbacks and height limits. Outside those zones, or where the site carries a qualifying overlay (natural hazards, heritage and similar section 6 matters), normal resource consent rules still apply.

How much does a granny flat cost to build?

A self-contained minor dwelling typically runs about $3,000 to $5,000 per square metre in NZ, so roughly $150,000 to $250,000 for a 50m² unit including services, with sleepout-style buildings much cheaper. Our cost guide breaks down the ranges and the price drivers.

Costs and consents

What a granny flat costs to build, with the price drivers and quote red flags, is in the granny flat cost guide. If your build does not fit the exemption (two storeys, over 70m², attached to the house), it needs a building consent: what that costs by council and how long it takes. The full legal detail is in our 70m² rules guide.

Sources: Building and Construction (Small Stand-alone Dwellings) Amendment Act 2025 and the National Environmental Standards for Minor Residential Units (in force 15 January 2026). This page summarises the rules as at 13 July 2026; confirm your specific project with your council or a building professional.