Yes, you can build a minor dwelling without a building consent under the 2026 rules, provided it’s new, detached, single storey, self contained, under 70 m² and built by licensed building professionals. You’ll still need a Project Information Memorandum before you start, and the NES-DMRU planning rules apply separately. Natural hazards, poor services access, or a non-compliant site can knock the exemption out entirely, so check both regimes before you commit to a design.
TL;DR:
- The exemption applies only if the minor dwelling is new, detached, single-storey, self-contained, under 70 m², and built by a licensed professional.
- Building and resource consents can still be required if site natural hazards, poor access, or non-compliance with standards apply, or if the project involves conversions or heavy construction.
- Size, height, and weight limits—such as a maximum 4-meter roof height, 1-meter floor level, no mezzanine, and lightweight framing—must be strictly met and carefully measured from finished internal surfaces.
- Both the building exemption and NES-DMRU planning standards must be checked separately, as they operate independently and may result in different consent requirements.
- Site conditions, such as wastewater capacity, natural hazard overlays, and service access, are critical factors that can automatically disqualify the exemption regardless of dwelling size.
Table of Contents
- What is a minor dwelling and who qualifies for the exemption?
- What changed in 2026: the exemption and NES-DMRU explained
- How are the size, height and material limits measured?
- What services and site conditions can block the exemption?
- When do you still need a building or resource consent?
- How do you apply the exemption process step by step?
- What must steel-frame kitset buyers confirm before manufacture?
- What do council fees and resale implications look like?
- Can you rent out a minor dwelling under these rules?
- Does building a minor dwelling improve your investment position?
- Do council rules on minor dwellings vary by region?
- What actually matters more than the paperwork
- How Steelframeman can help you build within the rules
- Where to check the official rules
- Sources
- FAQ
What is a minor dwelling and who qualifies for the exemption?
A minor dwelling, in the language of the amended Building Act, is a “small stand-alone dwelling”: a compact, self-contained home built on the same site as an existing house, intended for one household, and separated from the main dwelling. It’s the legal cousin of what most Kiwis call a granny flat or sleepout, but the statute is specific about what counts.
To qualify for the building consent exemption, your project needs to tick every one of these boxes:
- New construction, not a conversion of an existing shed, garage, or sleepout
- Detached from the main house, single storey, with no mezzanine floor
- Self-contained, with its own kitchen, bathroom and sleeping space for one household
- No more than 70 m² measured internally between finished wall faces
- Designed and built, or supervised, by a Licensed Building Practitioner (LBP)
- Meets minimum separation distances from the main dwelling and boundaries
Miss any one of these and you’re back in standard building consent territory, with all the paperwork and cost that involves.
What changed in 2026: the exemption and NES-DMRU explained
Two separate rule changes matter here, and confusing them is the single biggest mistake homeowners make. The granny flats building consent exemption commenced on 15 January 2026 under Schedule 1A of the Building Act. It removes the need for a building consent for qualifying small dwellings, but it does not touch resource consent or district plan rules.
That’s where the National Environmental Standards for Detached Minor Residential Units (NES-DMRU) comes in. It’s a nationwide permitted-activity framework that lets you build one detached minor residential unit up to 70 m² without resource consent, as long as it meets standards on things like height, setbacks and site coverage.
The two regimes run independently:
- Building Act exemption covers whether you need a building consent
- NES-DMRU covers whether you need a resource consent under the district plan
- You can pass one and fail the other, so both must be checked before design work starts
- Council overlays (heritage, flood, coastal hazard) can override NES-DMRU permitted status regardless of size
How are the size, height and material limits measured?
The 70 m² cap is measured between finished internal wall faces, not the outer frame dimensions. That distinction catches people out more often than any other rule. If your design includes an internal garage, laundry, or storage nook, it counts toward that 70 m², and a plan that looks comfortably under the limit on paper can tip over once internal linings go on.
Beyond floor area, the technical limits are tight and unforgiving:
- Maximum height of 4 metres from the supporting ground to the highest point of the roof
- Maximum floor level of 1 metre above the supporting ground, ruling out raised platform designs
- No mezzanine floors permitted under any circumstance, even a small sleeping loft
- Lightweight framing and roof cladding, with weight limits set out in Building Performance’s technical requirements for exempt work
- Minimum 2 metre separation from the principal dwelling and from site boundaries, per BRANZ’s technical bulletin
A design that looks small and simple on the plan can still fail the exemption if the roof is a heavy tile system, or if the floor sits 1.2 metres up on piles to manage a sloping site. Both are common choices for a standard sleepout, and both can force you into a full consent pathway.
What services and site conditions can block the exemption?
Water, wastewater, stormwater and power all need to connect properly, and that’s rarely as simple as running an extension cord from the main house. Where a network utility operator (NUO) service is available, you’re expected to connect to it. Where it isn’t, an on-site system has to meet acceptable solutions under the Building Code, and a poorly specified septic or greywater system is one of the fastest ways to trigger a resource consent requirement instead of sailing through on exemption.
A few practical checks matter early:
- Confirm wastewater capacity and connection point with your council or NUO before finalising the design
- Check vehicle crossing approval if the site doesn’t already have one, since this affects PIM sign-off
- On-site wastewater systems that exceed permitted discharge volumes usually push the project into resource consent territory
- Natural hazard overlays (flooding, liquefaction, coastal erosion) can rule out the exemption entirely regardless of dwelling size
None of this shows up on a floor plan, which is exactly why it catches people out at the PIM stage rather than the design stage.
When do you still need a building or resource consent?
Certain triggers pull a project straight out of exempt territory, no matter how small the footprint.
- Conversions and alterations to an existing structure, rather than genuinely new construction, always need consent.
- Any mezzanine, loft, or raised sleeping platform disqualifies the project immediately, even if the base footprint is well under 70 m².
- Heavier construction methods, such as masonry veneer or concrete tilt panels, that exceed the lightweight framing and roofing weight limits.
- Exceeding the 4 metre height or 1 metre floor level limits, often from a sloping site or a design with raked ceilings.
- Failing NES-DMRU standards on setbacks or site coverage, even where the building consent exemption itself is satisfied.
- Earthworks, subdivision, or protected natural or heritage features on the site, which always require a separate resource consent process.
Run through this list before you finalise a design, not after you’ve ordered materials.
How do you apply the exemption process step by step?
The process runs in a fixed order, and skipping ahead is where most delays happen.
- Apply for a Project Information Memorandum (PIM) from your local council before any physical work starts. Include your site plan, proposed dwelling design, and services layout. Councils charge a fee for this and may issue development contribution notices alongside it, so budget for both.
- Engage Licensed Building Practitioners for restricted building work, including foundations, framing and weathertightness. Collect Certificates and Records of Work from each trade as the build progresses, not retrospectively.
- At completion, notify the council and provide as-built plans, Records of Work, and all certificates within 20 working days. Pay any outstanding development contributions at this point.
Pro Tip: Keep a single, permanent project file from day one, PIM correspondence, producer statements, Records of Work, photos of concealed framing before it’s lined. For anything involving a slab, wastewater connection, or bracing you’re unsure about, a third-party quality assurance check before lining-up costs far less than a dispute at resale.
What must steel-frame kitset buyers confirm before manufacture?
The lightweight framing rule applies to the whole assembled system, not just the frame. A steel frame is naturally light, but if it’s paired with a heavy concrete tile roof or a thick masonry-look cladding, the finished building can still fail the exemption’s weight thresholds. That’s a detail easy to miss when you’re choosing a roof profile for looks rather than compliance.
Before manufacture starts, confirm the following with your designer or supplier:
- Design documentation suitable for the PIM application, including elevations, floor plans and a site plan
- Bracing calculations and the foundation interface, since this is where inspectors and lenders look hardest
- Service routing for water, wastewater and power, planned before the frame is fixed in place
- Producer information and Records of Work templates ready to complete as construction proceeds
Steelframeman supplies kitsets and pre-assembled panels nationwide, but final exemption eligibility always comes down to your specific site and what your council’s PIM confirms, not the frame alone.
What do council fees and resale implications look like?
Even an exempt build isn’t free of council involvement, and the fees catch people off guard. The PIM application itself carries a council fee, and many councils bundle a development contribution notice with it, a charge levied because a new dwelling adds demand on local infrastructure like water and roading. These contributions vary significantly by council and by zone, so ask for a written estimate at PIM stage rather than assuming a flat rate.
Insurance is where exempt builds get complicated later. Insurers generally want to see the same paper trail a consented build would produce, PIM approval, Records of Work, and completion certificates, before they’ll cover the structure without question. Turn up at claim time with nothing but a verbal assurance that “it met the exemption” and you may find cover disputed or reduced.
Resale carries the same risk in reverse. A Land Information Memorandum (LIM) pulled by a buyer’s solicitor will show whether the council received the required notification and paperwork for exempt work. A missing or incomplete file doesn’t necessarily kill a sale, but it gives buyers and their lenders a reason to negotiate hard, or walk. Lenders financing a purchase that includes an exempt minor dwelling often ask the same questions an insurer would: where’s the PIM, where are the certificates, who signed off the wastewater connection.
None of this means the exemption is a bad option financially. It generally still costs less and moves faster than a full building consent. It just means the savings only hold up if you treat the documentation with the same seriousness a consented build demands.
Can you rent out a minor dwelling under these rules?
Nothing in the building consent exemption or the NES-DMRU prevents you from renting a compliant minor dwelling to a tenant, but the exemption doesn’t relax any tenancy law obligations either. Once you’re renting, the Residential Tenancies Act and the Healthy Homes Standards apply in full, covering heating, insulation, ventilation, draught-stopping and moisture control.
A self-contained minor dwelling built to the 70 m² exemption still needs a compliant kitchen, bathroom and sleeping area to be legally habitable as a rental, exactly what the “self-contained” eligibility test already requires. Where landlords sometimes trip up is assuming that because the building didn’t need a building consent, it’s somehow held to a lower habitability bar than a consented dwelling. It isn’t. Tenancy compliance is assessed against the finished building, not against how it was consented.
Smoke alarms, insulation statements, and a healthy homes compliance statement all need to be in place before you advertise the unit for rent, the same as for any other rental property in New Zealand. If the minor dwelling shares a water or wastewater connection with the main house, your tenancy agreement should also be clear about how those shared services and any associated costs are managed between the two households.
Local district plans occasionally add conditions specific to minor dwelling rentals, particularly around parking provision or short-term letting restrictions in high-demand areas, so check your council’s district plan rules before listing the property, not after signing a tenant.
Does building a minor dwelling improve your investment position?
A compliant minor dwelling adds a second, separately lettable income stream to a single title, which is the main reason investors have taken an interest since the 2026 exemption commenced. Rental income from a self-contained unit can materially improve a property’s cash flow, and for owners with grown children or ageing parents, it adds flexibility without subdividing the land.
Financing is where the picture gets more nuanced. Most banks will lend against the value a minor dwelling adds to the property, but they typically want to see the same compliance paper trail insurers ask for: PIM approval, Records of Work, and completion notification to council. A minor dwelling built without any of that documentation is difficult for a valuer to credit at full value, because there’s no verifiable record it meets the Building Code.
Some lenders also treat an exempt minor dwelling more conservatively than a consented structure when calculating rental income for servicing purposes, since there’s no consent-based certificate of code compliance to point to. Ask your bank early, before you order materials, how they’ll treat the completed structure for valuation and lending purposes. That single conversation can shape whether you build to the minimum exemption specification or add a bit more, insulation upgrades, better wet-area waterproofing, purely to satisfy a valuer’s checklist later.
Do council rules on minor dwellings vary by region?
They do, and it’s one of the more overlooked parts of the exemption. The Building Act exemption itself is national and doesn’t change from council to council, but NES-DMRU permitted standards interact with each district plan’s own zone rules, and that’s where regional variation shows up.
Some councils in higher-density urban zones apply stricter site coverage or setback rules that push a minor dwelling into resource consent territory even where the NES-DMRU’s default standards would permit it. Coastal and flood-prone councils frequently overlay natural hazard rules that block the exemption on specific sites regardless of dwelling size, a rule that has nothing to do with the building itself and everything to do with the land it sits on.
On the other end, some regional and rural councils have signalled more flexibility on separation distances or vehicle crossing requirements for large rural sections, recognising that a 2 metre boundary setback matters less on a ten-hectare block than it does on a suburban quarter-acre. There’s no substitute for calling your specific council’s building or planning team before finalising a design. A rule that’s a non-issue in one district can be a hard stop two council boundaries over.
What actually matters more than the paperwork
People fixate on the “no consent needed” headline and skip past the part where they’re still fully responsible for the building meeting the Building Code. That responsibility doesn’t disappear because a form wasn’t lodged, it just shifts the risk from council inspection to your own diligence, and your LBP’s.
My honest view: if your site has anything remotely tricky, a slope, a shared wastewater line, a flood overlay, pay for the full consent anyway. The exemption suits straightforward sites with a competent LBP and clean services access. Lenders and insurers will ask for the same records either way, so build the paper trail as if you’ll need it, because you probably will.
— Rishi
How Steelframeman can help you build within the rules
Getting the size and weight limits right on paper is one thing. Getting a kitset that actually lands inside the 70 m² exemption once it’s framed, clad and roofed is another problem entirely, and it’s the one Steelframeman solves. Our Tiny House Steel Frame Kitset – 2.95m x 8.0m sits comfortably within exemption territory at 23.6 m², and larger options like the Tiny House Steel Frame Kitset – 2.95m x 10.2m or the Tiny House Steel Frame Kitset – 3.0m x 8.0m give you room to move without tipping over the internal measurement threshold, provided your finishing choices stay lightweight.
Every kitset comes with design documentation suitable for a PIM application, and the supplier’s team can talk through bracing, foundation interface and service routing before you commit to a layout, providing the detail your LBP will need for Records of Work. If a garage-style structure suits your section better, the Garage Steel Frame Kitset – 5.4m x 5.5m (29.7sqm) and Garage Steel Frame Kitset – 5.4m x 5.9m (30sqm inside frame) are worth a look too. Get in touch through our predesigned framing kitsets range for a quote, or request a design check before you lodge your PIM.
Where to check the official rules
- Building Performance’s granny flats exemption guidance sets out the full exemption conditions councils use to assess your project.
- The NES-DMRU legislation covers the resource consent side, separate from the building exemption.
- Your local council’s PIM application page (Horowhenua District Council’s is a useful example) shows what a typical PIM process and fee structure looks like.
- The Licensed Building Practitioners update confirms LBP obligations and the exemption’s commencement date.
Sources
- Granny flats exemption guidance | Building Performance
- National Environmental Standards for Detached Minor Residential Units 2025 | Ministry for the Environment
- Granny flats building consent exemption becomes law | Licensed Building Practitioners
- Apply for a Project Information Memorandum (PIM) | Horowhenua District Council
FAQ
Can I put a minor dwelling on my property in NZ?
Yes, provided it’s a new, detached, single-storey, self-contained dwelling for one household under 70 m², built or supervised by a Licensed Building Practitioner. You’ll still need a Project Information Memorandum and must confirm the site meets NES-DMRU planning standards separately.
Can a minor dwelling have a kitchen?
Yes, a full kitchen is expected. The exemption specifically requires the dwelling be self-contained, which means its own kitchen, bathroom and sleeping space, not a shared arrangement with the main house.
What is the definition of a minor dwelling?
Under the amended Building Act, it’s a small stand-alone dwelling: new, detached, single storey, self-contained, intended for one household, and no larger than 70 m² measured between finished internal wall faces, with no mezzanine floor permitted.
Can I put a tiny home on my property in NZ?
A tiny home on a permanent foundation can qualify for the same exemption as any other minor dwelling if it meets the size, height and lightweight construction limits. A tiny home on wheels is generally treated differently and may fall outside the exemption entirely, so confirm its classification with your council before ordering a kitset.
