What is a kitchen extension?
A kitchen extension is an extension designed around a new kitchen, usually an open-plan kitchen, dining and family space at the back of the house. We build the extension and fit the kitchen as one project, so plumbing, electrics and lighting are planned around the layout from the start.
How much does a kitchen extension cost in Barnet?
In Barnet, a kitchen extension typically costs £2,900–£4,400 per m² including a mid-range kitchen, including VAT at 20% (standard rate). For a typical 22 m² project that is roughly £64,000–£97,000. That range is adjusted for London, where domestic building work typically costs around 30% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (15 m²) | £43,500–£66,000 |
| Typical project (22 m²) | £64,000–£97,000 |
| Larger project (31 m²) | £90,000–£136,500 |
| Rate per m² | £2,900–£4,400 |
What moves the price most:
- Extension size and roof design
- Underfloor heating and flooring
- Who supplies the kitchen
- Kitchen units, worktops and appliances
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a kitchen extension in Barnet?
Whether you need planning permission depends on your house and its location in England. In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
On a typical kitchen extension we handle:
- Extension structure, roof and glazing
- Flooring and decoration
- Kitchen layout planned alongside the extension design
- Building control sign-off
- Extraction ducted to outside
- Kitchen fitting, worktops and splashbacks
How long does it take?
Allow 11 to 16 weeks on site, including kitchen fitting. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in Barnet
Many London boroughs have conservation areas and detailed design guides, so early design advice saves time at the planning stage.
Our Barnet coverage includes postcode districts EN5, and we also work in nearby places such as Potters Bar, Mill Hill and Borehamwood.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about kitchen extensions in Barnet
Can I buy my own kitchen?
Yes. You can supply it and we fit it, or we supply it as part of the price. Either way we coordinate deliveries with the build programme.
Do I need extraction to outside?
Building regulations require kitchen extract ventilation. Ducting to an outside wall is the most effective option and is planned during the build.
Should the kitchen be designed before the extension?
Yes. Knowing where the sink, hob and island will go lets us place drains, ducting, sockets and windows correctly during the build.
How much does a kitchen extension cost in Barnet?
In Barnet, a kitchen extension typically costs £2,900–£4,400 per m² including a mid-range kitchen, including VAT at 20% (standard rate). A typical 22 m² project comes to roughly £64,000–£97,000. Your fixed price depends on the survey and drawings.
Who approves a kitchen extension in Barnet?
Planning matters in Barnet go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.