Quick answer
The line between a sleepout and a minor dwelling in New Zealand is self-containment, not size. A sleepout has no cooking facilities, no sanitary facilities and no potable water storage of its own — it borrows the main house's bathroom — which is why it goes up under a Building Act Schedule 1 exemption with no building consent. Add a kitchen and a bathroom and it becomes a self-contained minor dwelling: classified use Housing – detached dwelling, the full Building Code, and either a building consent or the granny flats exemption that began on 15 January 2026. That exemption is new-build only, so adding the kitchen later is a consent job.
Key points
- Cooking plus sanitary facilities tip a sleepout into a dwelling — MBIE says sleepouts and garages are not dwellings because they cannot be self-contained.
- Every Schedule 1 detached-building exemption caps you at 30 square metres and bars sanitary facilities, potable water storage and cooking where people sleep.
- A minor dwelling is classified Housing – detached dwelling, which drags in the full Building Code: G3, G4, G12, G13, E3, H1 and F7 all touch the kitchen.
- The granny flats exemption allows one self-contained dwelling up to 70 square metres with no consent — but it is new-build only, never a conversion.
- There is no code compliance certificate at the end of an exempt granny flat, which becomes your insurer's question and then a buyer's solicitor's.
Self-containment is the test. Not size, not looks.
Somebody in Papatoetoe rings around for a 24 square metre sleepout for the back of the section. Two suppliers quote a kitset, no consent, on the ground in a fortnight. He is picturing his mother-in-law in it, or — more honestly — a tenant. Then he says the sentence that costs more than the sleepout: we'll just add a kitchenette later.
We manufacture out of East Tamaki and see the back end of this constantly, usually when someone wants a benchtop dropped into a building never designed to carry one. We are not your LBP and not your council. What follows is the Building Act and MBIE's guidance; your district plan sits on top.
Self-containment is the test, not square metres
MBIE and the councils draw the line in the same place, and it has nothing to do with how the building looks from the driveway. The granny flats guidance is blunt: sleepouts, garden sheds and garages "are not considered dwellings as these do not have all the necessary facilities to be self-contained", giving a bathroom or a kitchen as the examples. So every Schedule 1 detached-building exemption carries the same three conditions: no sanitary facilities, no facilities for the storage of potable water, and — where there is sleeping accommodation — no cooking facilities at all. MBIE gives the reason for the cooking ban in four words: the risk of fire. Clause A1 then sorts outbuildings, the ones not intended for human habitation, from Housing, and a granny flat is explicitly Housing – detached dwelling. A sleepout sits in the middle: someone sleeps in it, but it leans on the house for the two things that make a home a home.
What the sleepout exemptions actually let you have
There is no single sleepout rule. Schedule 1 gives a family of detached-building exemptions, and which one you land in depends on size, materials and who did the design.
- Up to 10 square metres, the plain route — single storey, floor no more than 1 metre above the supporting ground, 3.5 metres max above that floor.
- 10 to 30 square metres, lightweight — walls and roof to Acceptable Solution B1/AS1, roofs under 20 kg per square metre, cladding under 30.
- 10 to 30 square metres, LBP route — design or construction carried out or supervised by a Licensed Building Practitioner.
- 10 to 30 square metres, kitset — the supplier must have had the design done or reviewed by a Chartered Professional Engineer.
- Every 10 to 30 square metre route needs 1 metre clear of any residential building and any boundary, plus smoke alarms where people sleep.
Notice what none of them allow. Not one route permits a sink, a toilet, a shower, a cylinder or a hob in a building people sleep in. A sleepout can have power and lights. It cannot have plumbing.
| Condition | Sleepout / cabin (Sch 1, cl 3 family) | Granny flat (Sch 1A, from 15 Jan 2026) |
|---|---|---|
| Maximum floor area | 30 m², or 10 m² on the plain route | 70 m², measured between the internal faces of the external walls; an attached garage counts |
| Cooking facilities | Barred where people sleep | Required — the exemption assumes a self-contained home |
| Sanitary facilities | Barred | Required |
| Potable water storage | Barred | Required; connected to the network utility operator where available |
| Clearance to boundary or dwelling | 1 m on the 10–30 m² routes | 2 m, and it cannot straddle an allotment boundary |
| Height | 3.5 m above floor level; floor ≤ 1 m above ground | 4 m above floor level; floor ≤ 1 m above ground |
| Storeys | Single storey | Single storey — a mezzanine disqualifies it |
| Classified use | Not a dwelling | Housing – detached dwelling |
| Council involvement | None required by the exemption | PIM before you start, notify on completion, no CCC |
| New build only? | No | Yes — no additions, alterations or conversions |
| Development contributions | Ask your council; no household unit is created | May apply, notified through the PIM |
What changes the second you add a kitchen
Once the building is a dwelling, the Building Code arrives in full. The kitchen alone touches most of the back half — G3 food preparation, G4 ventilation, G12 water supplies, G13 foul water, E3 internal moisture, F7 warning systems, and G1 and G2 once one wet wall carries the bathroom and laundry too. That is the difference between a 3000 mm run with a properly graded waste and a ducted extract through the soffit — and the same cabinetry with a flexi hose into a gully trap someone found on YouTube. If you know what the Healthy Homes standards ask of a landlord's kitchen, the extraction rule is familiar; the Code version bites earlier, because it applies whether or not there is ever a tenant.
The granny flats exemption, and what it actually costs you
From 15 January 2026 you can build one detached, single-storey, self-contained dwelling up to 70 square metres with no building consent, under Schedule 1A. The conditions are tighter than the headline suggests. New build only. Light timber or light steel framing. No mezzanine. Two metres clear of everything. Restricted building work still done or supervised by an LBP.
The plumbing conditions are where kitchen designs quietly fail. The flat is capped at 30 fixture units. Main drains must be DN100 or larger at a minimum 1:60 grade, branch drains DN65 at 1:40. No pumped systems inside the building — which kills the macerator-under-the-sink fix people reach for when the fall is wrong. Want a solid fuel heater or a level-entry shower? You are out of the exemption and into a consent. And with no consent the council does no inspections and issues no code compliance certificate: you get a PIM at the start, finish within two years, and file final plans, Records of Work and the electrical and gas certificates within 20 working days. Compliance is legally yours.
Why "we'll add a kitchenette later" is the expensive sentence
Here is the trap. The granny flats exemption is available only for a new build. MBIE says it cannot be an addition, an alteration or a conversion, and names existing garages and sleepouts as outside it. So the plan — exempt sleepout now, kitchenette next year, call it a minor dwelling — does not work. Add the kitchen and you have created a dwelling; because the building already exists, the one exemption that would have covered a dwelling is shut to you. The consent then has to deal with a building framed to sleepout rules: 3.5 metres of height, maybe a metre off the boundary, no drainage under the slab, no thought given to H1. Often the cheapest honest answer is to leave it as a sleepout, or start again at 70 square metres.
Every sleepout we get called back to has the same thing behind the lining — a cold-water pipe someone ran 'just in case', and no paper anywhere saying it's there.
Decide the kitchen before you pour the slab.
Designing a kitchen for 70 square metres — and for a tenant
Seventy square metres is not much once you have taken out a bedroom, a bathroom and a hallway. The kitchen usually gets three to four linear metres along one wall, sometimes an L into the living end. Forget the scullery — a butler's pantry laid out properly needs floor area this build does not have. An island is out too: the 1000 mm clearances that make one work eat the living space you are protecting. The discipline behind standard cabinet sizes in a townhouse applies with less room to be wrong.
If it is going to be rented, the extraction is not negotiable. The Healthy Homes ventilation standard wants an extractor venting outside; recirculating units do not meet it, and a new rangehood over a cooktop needs a minimum 150 mm diameter including ducting, or at least 50 litres per second. The argument is in ducted versus recirculating rangehoods, and with a bedroom two metres from the hob it is not close. Spec the rest as rental kitchen materials that survive suggests, and lean on making a small kitchen feel bigger.
What goes wrong
- The plumbing goes in "for later". A waste and a cold feed get run on the theory it is not a kitchen until the sink lands. It is unconsented plumbing in a building not allowed to have it, and it surfaces the day someone reads the LIM.
- The kitchenette gets called a kitchenette. No threshold in the Act makes a hob stop counting — a sink and a cooktop is cooking and sanitary facilities, whatever the drawing says.
- The drainage grade was never possible. The flat gets sited at the low corner, then the main drain cannot make 1:60 without a pump — and pumps inside the building are outside the exemption.
- The 70 square metres includes the garage. Owners design to 70, attach a single garage, and discover it counts. The kitchen gets shrunk to claw the metres back.
- No CCC, no finance. The build is fine, the file is not — and the bank wants evidence nobody kept.
What to ask before you sign anything
- Is this building ever intended to be self-contained — now, or within five years? A maybe is a yes, and you design it as a dwelling from day one.
- Which exemption are we relying on, by name? A supplier who cannot say whether it is the lightweight route or Schedule 1A is guessing.
- Does the plan reach 70 square metres including any attached garage, and has the PIM been applied for?
- Can the drainage make grade by gravity, no pump inside, inside 30 fixture units?
- Where does the rangehood duct terminate, and who makes that penetration?
- Who issues the Records of Work, and has council confirmed development contributions?
Frequently asked questions
Can I build a sleepout now and add a kitchen later to make it a minor dwelling?
Not under the granny flats exemption. MBIE is explicit that Schedule 1A applies only to new builds and cannot be used for an addition, alteration or conversion, and it names existing sleepouts and garages as outside its scope. Adding the kitchen creates a dwelling, so you would be applying for a building consent on a building never designed to dwelling standards.
What exactly makes a building a minor dwelling rather than a sleepout in NZ?
Self-containment — having its own cooking and sanitary facilities so it can work as a home independently of any other building. MBIE says sleepouts, sheds and garages are not dwellings because they lack the facilities to be self-contained, and councils including Auckland Council treat a building with a kitchen and a bathroom as a self-contained minor dwelling. Floor area and what you call it on the drawing are irrelevant.
Can I put a sink and a microwave in a sleepout without a consent?
A sink needs water and a waste, which takes you outside the Schedule 1 exemptions — they bar sanitary facilities and potable water storage outright. A microwave on a bench is not a fixed cooking facility the way a hob is, but the exemptions also bar cooking facilities in any building with sleeping accommodation. Get your council or LBP to confirm in writing first.
Do I still need a resource consent for a granny flat if the building consent is exempt?
Possibly. The building consent exemption sits under the Building Act while planning sits under the RMA, and MBIE states the two operate independently. The National Environmental Standards for Detached Minor Residential Units, in force from 15 January 2026, make one detached minor residential unit per site a permitted activity in residential, rural, mixed use and Māori purpose zones if you meet the standards. Your site could clear those and still need a building consent.
Will a granny flat built without a consent cause problems when I sell or insure it?
It can, and the risk is documentary rather than structural. No building consent means no council inspections and no code compliance certificate, so there is no sign-off to point at. MBIE notes insurers and lenders will still want assurance and may ask for final plans, Records of Work, Certificates of Work and proof development contributions were paid.
Send us the layout, we'll send back a number
If you have a sketch of a 70 square metre flat, or a floor plan from a design-build outfit, send it through. We price the kitchen off it — cabinetry, benchtop, hardware, appliances if you want us handling them, delivered and installed — and it comes back inside 24 hours. A rough scope gets a real number; drawings sharpen it. No showroom is why it is a trade number, one contract and one invoice.
We will also tell you if the kitchen you have drawn cannot be built where you have drawn it — the waste that will not make grade, the rangehood with nowhere to duct, the tall bank that puts you over 70. Cheaper now than after the slab. Twenty-three years out of East Tamaki, 2000-plus kitchens, Site Safe qualified. Send the plan and tell us whether the thing is a sleepout or a dwelling. If you are not sure, that is the first thing to sort out.