Kitchen extensions in Friern Barnet: design, approvals and build
Friern Barnet homeowners can use us for the whole kitchen extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in Friern BarnetFrom £35,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsN2, N3, N10, N11, N12

Guide prices for Friern Barnet
Prices below are for Friern Barnet, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Friern Barnet: £2,340 to £4,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £35,000 – £41,000 | £40,500 – £52,000 | £51,500 – £68,500 |
| 4 m × 5 m 20 m² | £46,500 – £55,000 | £54,500 – £69,000 | £68,500 – £91,000 |
| 4 m × 7 m 28 m² | £65,500 – £76,500 | £76,000 – £96,500 | £96,000 – £127,500 |
Build cost only. A mid-range kitchen, supplied and fitted, typically adds £9,000 to £20,000.
Try the guide-price tool to see a range for your own size and finish.
Planning rules that apply in Friern Barnet
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extensions in and around Friern Barnet
We cover Friern Barnet and the postcode districts N2, N3, N10, N11, N12, N20. Neighbouring towns we cover include Muswell Hill (2 miles), Finchley (2 miles), Wood Green (2 miles), Palmers Green (2 miles).
Potters Bar, in Hertfordshire, is roughly 6 miles from Friern Barnet and also on our list. London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
Included in a typical project
- Wide sliding or bifold doors to the garden
- Roof lantern or rooflights positioned over the work zones
- Drainage and services designed for sinks, island and appliances
- Kitchen-led layout planning before the drawings are fixed
- Extraction routes and ventilation for building regulations
What happens next
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Kitchen extension questions answered
Will my neighbours in Friern Barnet be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Who do I contract with for a kitchen extension in Friern Barnet?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How long does a kitchen extension take to build in Friern Barnet?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Can you fit a kitchen I buy elsewhere?
Yes. We can fit it or work with your supplier’s fitters. We need the layout early so that drains, services and lighting are in the right place.
Where should the island go?
Usually under the brightest part of the roof and away from the main walkway to the garden. We test two or three layouts on the plan before deciding.
Book a free site visit in Friern Barnet
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.