Quick answer
In a 70m² granny flat the kitchen gets one wall of about 3.0 to 3.6 linear metres, because the bedroom, bathroom and living space take the rest. Put the sink, dishwasher and cooking zone on that run, and add a peninsula if you can still leave roughly a metre to walk past — sized right, it replaces the dining table and buys the bench the wall cannot. A galley needs 1200mm clear between two runs, which most 70m² plans cannot spare. Forget the scullery. And build the fridge cavity to the install guide's cabinetry dimension, not the fridge width: a 905mm fridge wants around 945mm of cavity and 1810mm of height.
Key points
- After a bedroom, bathroom and living space, a 70m² granny flat leaves the kitchen one wall of 3.0 to 3.6 linear metres.
- A galley wants 1200mm of clear floor between the runs; under 1000mm the dishwasher and oven doors collide.
- A peninsula is the only move that buys bench without buying wall, and it deletes the dining table from a room with no space for one.
- A 450mm dishwasher hands back 150mm of bench — on a 3.6m run, a 27 percent lift in your entire prep surface.
- The exemption demands a single storey, no mezzanine, under 4 metres high and no pumped systems inside, so gravity decides where your sink goes.
One wall, three answers, three different benches.
There is a version of this job on half the back sections in Papatoetoe, Te Atatū and Glen Innes. Mum is coming out of a two-storey place she can no longer manage, the back lawn has done nothing for fifteen years, and since 15 January 2026 you can put a self-contained dwelling of up to 70m² on it with no building consent and no resource consent. The plan comes back and the kitchen is a dashed rectangle labelled KIT. Nobody has counted a millimetre.
This is about those millimetres. The paperwork still stands — a Project Information Memorandum before you start, licensed building practitioners carrying out or supervising the work, registered tradespeople on the plumbing, Building Code compliance, notify council on completion, development contributions. Confirm it with your council and your LBP. What follows is the part nobody plans: the layout that suits your mother in 2026 is not the one that suits whoever rents it in 2033.
Start with the wall you have, not the room
Seventy square metres sounds like plenty until you subtract a bedroom, a bathroom, a laundry cupboard, an entry and a hallway. But the number that decides your kitchen is not square metres, it is linear metres. One wall has the slider, one has the window you need for light, one has the doorway to the bedroom, and one has to hold a sofa. What survives is usually a single stretch of 3.0 to 3.6 metres. Do the sums on 3.6: a fridge cavity takes about 950mm, the sink cabinet 900mm, the cooking zone 600mm, a dishwasher another 600mm. That is 3,050 of your 3,600 gone, leaving 550mm of clear bench — one chopping board, and the entire preparation surface of the dwelling. Read the layout families first; everything here is built on standard NZ cabinetry sizes.
Single run, galley, or peninsula
Three layouts are genuinely available at this size. A single run is the default: honest, cheap, cramped. A galley gives the most bench per square metre of any layout ever drawn, which is why boats use it — but it needs a corridor, and a corridor here is floor taken off the lounge. A peninsula is a single run with a leg into the room, and it is the only one that adds bench without adding wall.
| Layout | What it needs | Clear bench | Where it falls over |
|---|---|---|---|
| Kitchenette (1.8–2.4m) | One short wall | Almost none | Fine for a guest. A tenant will resent it. |
| Single run (3.0–3.6m) | One wall only | Roughly 0.5–0.7m | No landing space beside the fridge or oven. |
| Single run + peninsula | Same wall, plus 1.5–2.0m into the room | Adds 1.2–1.8m, seats two | Eats floor. Get the walkway wrong and you have a bottleneck. |
| Galley (two runs) | Two facing walls, 1200mm clear between | The most — 1.8m plus | Under 1000mm, opposing doors collide. Takes a wall off the lounge. |
Our position, and we will defend it: at 70m², a single run with a well-sized peninsula beats a galley almost every time. The galley wins on paper and loses in the room, because the 1200mm between the runs comes straight out of the living space. Run the cabinetry along the wall, bring a leg off one end 1.5 to 2.0 metres long, give the room side an overhang deep enough for knees — around 300mm — and two people eat there. Nobody buys a table. The sizing rules for islands and peninsulas transfer directly, except that here you have no margin.
600 or 450: the dishwasher argument
A standard dishwasher is 600mm wide. A slimline is 450mm, generally the same height and depth, and takes a few place settings fewer. On a 3.6m run, dropping to a 450 gives back 150mm of bench — nothing, until you remember you only had 550mm. It is a 27 percent increase in the entire preparation surface of the home.
The honest split: if your wall is 3.6m or better, fit the 600 — you will find the 150mm elsewhere, and the 600 is what the market expects. If your wall is 3.0m or under, stop pretending. Fit the 450, put the 150mm into bench, and be at peace with it. Where the 450 bites is the long game, because granny flats get rented to whoever answers the ad.
Size the fridge cavity for the tenant, not your mother
Read this twice, because it is the only mistake here that cannot be fixed without pulling cabinetry apart. Your mother has a top-mount fridge, around 680mm wide, going since the Clark government, so the plan gets a 700mm fridge space and everyone moves on. Five years later the flat is tenanted, and the tenant arrives with a French door fridge 905mm wide. It does not go in.
It is worse than the raw width suggests, because a fridge does not fit a cavity its own size. Fisher & Paykel's install guide for one of its 905mm quad-door models lists the product at 905mm wide and 1790mm high — but the cabinetry dimension, the clear cavity including minimum air clearances, is 945mm wide and 1810mm high, with 20mm at the sides, 30mm at the rear and 50mm of venting above.
A 905 mm fridge does not fit a 900 mm hole.
So build for the fridge you do not own yet. Around 950mm clear width and at least 1800mm of height covers most of what is sold in Auckland. Yes, it costs you bench, and on a 3.6m run that hurts. Take it anyway. A cavity 100mm too generous costs you a drawer; 40mm too tight costs you a fridge.
Every granny flat plan we price has the fridge drawn as a 900 square. The fridge they actually buy is 905 and wants 945 of cavity. That call always comes on install day, and by then the gables are screwed to the floor.
What the exemption does to your kitchen
The exemption is not free. It buys speed by imposing a shape. Single storey, no mezzanine — so the loft you were going to put over the kitchen disqualifies the whole dwelling, not just the loft. Maximum height 4 metres above floor level. Two metres or more from other residential buildings and legal boundaries. Self-contained, to the Building Code for a detached dwelling.
Two conditions matter most. The first caps total fixture units at 30 — alarming until you count it up, and a typical one-bedroom lands around eighteen, so nobody should talk you out of a dishwasher on those grounds. The second is the real one: no pumped systems inside the building. The main drain must be at least DN100 at a minimum grade of 1:60, branch drains at least DN65 at 1:40. Gravity does all the work, so where the drain comes up decides where your wet cabinets go — settled before the slab is poured.
| Fixture | Discharge units | Min trap & pipe (mm) |
|---|---|---|
| Kitchen sink (domestic, single or double) | 3 | 40 |
| Dishwashing machine (domestic) | 3 | 40 |
| Water closet pan | 4 | 80 |
| Shower | 2 | 40 |
| Basin | 1 | 32 |
| Laundry (tub, with or without washing machine) | 5 | 40 |
| Typical total | 18 of 30 | — |
Extraction, and the day it becomes a rental
A recirculating rangehood solves nothing except the visual. A charcoal filter takes some of the grease and none of the moisture, and in a 70m² dwelling that moisture has nowhere to go but the bedroom wall — so duct it outside. There is a compliance edge too. The moment the flat is tenanted the Healthy Homes standards apply: for a room with a cooktop, a new fan or rangehood needs a minimum diameter of 150mm including the ducting, or an exhaust capacity of at least 50 litres per second, venting outdoors. Recirculating units do not meet it, and the wider Healthy Homes obligations are worth reading even if you are building for family.
What goes wrong
- The fridge cavity is built to the fridge width. Someone reads 905, builds 910, and the fridge needs 945.
- The sink goes under the window on the wrong wall, gravity does not oblige, and someone proposes a pump — which the exemption forbids inside.
- The peninsula is set 900mm off the run because it fitted on the drawing. Open the dishwasher and the walkway is gone.
- No landing space beside the oven. Everything hot goes down on the cooktop, and the benchtop beside it is scorched inside a year.
- Overheads run to a 2.4m ceiling in a dwelling built for someone in their seventies. The top shelf tempts a step stool.
- The laundry gets shoved into the kitchen run late. A washing machine is 600mm of your 3,600 and five discharge units.
The thread through all six: the kitchen was designed last, after the walls were fixed. In a house you absorb that. At 70m² there is no slack. And the scullery question, since everyone asks — no. A scullery needs three to four square metres plus a door swing, which here means giving up most of a bedroom.
What to ask before you sign
- What is the clear wall length for the kitchen run, measured between finished surfaces rather than framing?
- Where does the foul water connection come up, and does the fall work by gravity to the sink, with no pump inside?
- What clear cavity width and height is the fridge space built to — from an install guide, or from memory?
- Is the rangehood ducted outside, and what is the duct diameter and extraction rate in litres per second?
- With the dishwasher and oven doors open, is there still a walkway from the front door to the bedroom?
- Is it supply and install under one contract, including the site measure, the scribing and the callback?
Frequently asked questions
How many linear metres of kitchen do you get in a 70m² granny flat?
Usually 3.0 to 3.6 linear metres of one wall. Once you subtract a bedroom, a bathroom, an entry, a hallway and a laundry cupboard, the living space keeps the remaining walls busy with a slider, a window, a doorway and a sofa. Measure the clear wall between finished surfaces — it is typically 300 to 400mm shorter than expected.
Can I put a scullery in a granny flat?
Realistically, no. A working scullery needs three to four square metres plus a door swing, and at 70m² that comes out of the bedroom or the living area. The better answer is a tall pantry with pull-out shelves, a proper bin drawer, and an appliance garage if you can spare 600mm.
Do I need a building consent for the kitchen in a granny flat?
Under the exemption that took effect on 15 January 2026, a new detached self-contained dwelling of up to 70m² can be built without a building consent or a resource consent, and the kitchen is part of that dwelling. It still has to meet the Building Code, and the work must be carried out or supervised by licensed building practitioners, with plumbing and drainage by registered plumbers and drainlayers. You still need a PIM before you start, must notify council on completion, and development contributions still apply.
Should I fit a 450mm or a 600mm dishwasher in a granny flat?
If the run is 3.6m or longer, fit the 600 — it is what tenants and buyers expect. If the run is 3.0m or shorter, fit the 450 and put the 150mm into clear bench, because on a run that short the bench is worth more than the place settings. The slimline is fine for one or two people; it becomes a complaint when a family moves in.
What size should the fridge cavity be in a granny flat kitchen?
Build to the cabinetry dimension in the install guide rather than the fridge width, and size it for a fridge you do not own yet. One Fisher & Paykel 905mm quad-door model is 905mm wide but asks for a clear cavity 945mm wide and 1810mm high, with 20mm side clearance, 30mm at the rear and 50mm of venting above. Around 950mm clear and at least 1800mm high keeps most wide fridges available to you.
Getting a number on it
A granny flat kitchen is a small job with no room for error, which is not the same as an easy job. The value is in someone counting the millimetres before the gables are fixed, and in one organisation owning the measure, the manufacture and the install — so when a cavity is 40mm out there is no argument about whose 40mm it was. Entry grade for a kitchen this size sits in the lower five figures, plus GST.
Send us the floor plan — a PDF, a sketch, or a photo of a drawing on the bonnet of the ute is genuinely fine. We will tell you the clear wall length, what fits on it, what the fridge cavity should be built to, and whether the peninsula you want leaves you a walkway. Trade-priced number back inside 24 hours, supply and install under one contract and one invoice, from our own workshop in East Tamaki.