Granny flat guide · 2026 law change
Build a granny flat without a building consent
From 15 January 2026, New Zealand law lets you add a self-contained granny flat of up to 70m² without a building consent — provided it is a simple design that meets the Building Code, is built or supervised by licensed professionals, and your council is notified before and after. Here is what the change means for you.
What has changed
Under the Building and Construction (Small Stand-alone Dwellings) Amendment Act 2025 — Schedule 1A of the Building Act 2004 — a compliant granny flat no longer needs a building consent. That removes one of the biggest cost and time barriers to adding a second dwelling. The home still has to meet the Building Code, and a few other rules still apply.
What qualifies
To use the exemption, your granny flat needs to tick all of these.
Up to 70m²
One self-contained dwelling, up to 70 square metres of floor area.
Simple design
A straightforward single-storey home that meets the New Zealand Building Code.
2m from boundaries
Set at least 2 metres from boundaries and from any other building.
Max 4m high
No taller than 4 metres from ground level.
Licensed professionals
Designed, built or supervised by licensed building practitioners, with registered plumbers, drainlayers and electricians.
Notify your council
Tell your council before you start and once it is finished — a PIM and records of work are part of the process.
The full qualifying criteria
To use the exemption, every one of these must be true.
- New build — not a conversion, addition or alteration to an existing building.
- Standalone — not connected to any other building.
- Single storey — no mezzanine or part-storey.
- 70m² or less of internal floor area.
- Self-contained — with its own kitchen, bathroom and toilet.
- For residential use — intended for a single household or family.
What doesn't qualify
Sleepouts, garages and sheds do not qualify, and neither do tiny houses on wheels.Design and building requirements
The granny flat must meet the New Zealand Building Code, along with these construction conditions.
Maximum height 4m
No more than 4 metres above floor level.
Floor level
No more than 1 metre above ground level.
2m setbacks
At least 2 metres from any boundary and any other residential building.
Light framing
Built using light timber or light steel framing.
Roof cladding
No heavier than 20kg/m² — e.g. metal sheet or membrane roofing.
Wall cladding
No heavier than 220kg/m² — e.g. timber weatherboards, AAC or clay masonry veneer.
Showers
Prefabricated acrylic units only — no wet-floor or level-entry showers.
Heating
No solid fuel heaters — heating must be electric or gas.
Services
Independent electricity supply, and gas supply if applicable.
Water, drainage and plumbing
Connect to council network utility operator (NUO) systems where available; otherwise an on-site system may be used. Plumbing and drainage must meet the Building Code acceptable solutions, plus these practical limits.
- No more than 30 fixture units.
- No pumped systems inside the building.
- Main drain no smaller than DN100 at a minimum 1:60 grade.
- Branch drains no smaller than DN65 at a minimum 1:40 grade.
- Upstream vents no smaller than DN65.
Licensed building professionals are required
All design and construction work must be carried out or supervised by licensed building professionals. This is a non-negotiable condition of the exemption — you cannot design or build the granny flat yourself unless you hold the appropriate qualifications.
- A Licensed Building Practitioner (LBP) designer or registered architect to prepare your plans.
- An LBP builder to carry out or supervise the construction.
- Licensed plumbers, drainlayers, gasfitters and electricians for the relevant trade work.
The PIM — your first step
Before any building work begins, you must apply for a Project Information Memorandum (PIM) from your local council. Work cannot start until the PIM is issued. It is an information document — not a consent or approval — and it tells you about:
- Any natural hazards on the site.
- Heritage status.
- Infrastructure and utility connections.
- District and regional plan requirements, including any covenants or consent notices on the title.
Natural hazards
If the site is affected by erosion, flooding, subsidence, slippage or falling debris, your design must adequately mitigate those risks. If adequate mitigation isn't possible, the exemption cannot be used and a building consent is required instead.
Resource consent and planning rules
The building exemption works alongside — but separately from — the resource consent system. You should also check the granny flat against the National Environmental Standards for Detached Minor Residential Units (NES-DMRU) under the Resource Management Act.
The NES-DMRU generally lets a detached minor residential unit proceed as a permitted activity in residential, rural, mixed-use and Māori-purpose zones, provided it meets the setback and other standards. Site-specific issues such as title encumbrances, consent notices or natural hazards can change this.
We can help
This is an area where specialist planning advice makes a real difference. We can help you navigate it for your property.What councils do — and don't do
Councils have a limited role under the exemption. They do not inspect the work, issue approvals, or provide a Code Compliance Certificate.
What councils do
- Issue the PIM within 10 working days.
- Provide information on site hazards, bylaws and planning rules.
- Receive and store your completion documentation.
- Issue a development contribution notice if applicable.
- Issue a Notice to Fix if the build is unsafe or non-compliant.
What councils don't do
- Inspect the building work.
- Issue approvals or sign-offs.
- Provide a Code Compliance Certificate.
Responsibility for meeting the Building Code sits with you as the homeowner and the licensed professionals you engage.
Completing the build
When construction is finished, the granny flat is legally complete once you have all the required documentation from your licensed professionals.
- Records of Work (RoW) from LBP builders and plumbers/drainlayers.
- Certificates of Work (CoW) from LBP designers.
- Electrical safety certificates.
- Gas safety certificates, if applicable.
20 working days to file
You then have 20 working days to submit this documentation, plus your final design plans, to the council that issued your PIM. Missing the deadline can result in fines. Development contributions, if required, must also be paid within 20 working days of completion.If things go wrong
Building outside the exemption conditions — or failing to meet the Building Code — can carry serious consequences.
Fines
Up to $200,000, plus $10,000 per day for continuing offences.
Insurance & finance
Difficulty getting insurance or finance, and reduced resale value.
Retrospective consent
A requirement to obtain a building consent after the fact, or apply for a certificate of acceptance.
Professional liability
Disciplinary action against the licensed building professionals involved.
What still applies
No building consent does not mean no rules. These still need to be checked for your property.
- Your district plan and Resource Management Act rules — a national standard to remove resource consent for compliant minor dwellings is being rolled out.
- Natural hazard rules, such as flood or land-stability overlays.
- Development contributions payable to your council.
- Any covenants or restrictions registered on your property title.
- Residential tenancy law, if you rent the granny flat out.
Designed around the new rules
Our 70 Ready™ range is purpose-built for the 70m² pathway — simple, Code-compliant designs, built and signed off by licensed professionals, with the council notifications handled for you.
This page is a general overview, not legal advice. Exemption conditions and timing are set by central and local government and can change — confirm the details for your property with your local council and the official guidance at building.govt.nz.