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 Hayes?
In Hayes, 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. We start from a UK-wide guide and adjust it for London, where labour and materials are typically about 30% above 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 |
The biggest cost drivers are:
- Who supplies the kitchen
- Island with sink or hob, which needs services in the floor
- Underfloor heating and flooring
- Kitchen units, worktops and appliances
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a kitchen extension in Hayes?
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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical kitchen extension we handle:
- Kitchen fitting, worktops and splashbacks
- Drainage and water supply positioned for the sink and appliances
- Building control sign-off
- Extraction ducted to outside
- Flooring and decoration
- Extension structure, roof and glazing
How long does it take?
Allow 11 to 16 weeks on site, including kitchen fitting. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Hayes
Victorian and Edwardian terraces dominate many London streets, which is why side return, wraparound and mansard projects are so common here.
From TW8 outwards, we take on projects throughout Hayes and the surrounding parts of Greater London.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about kitchen extensions in Hayes
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.
Do you build kitchen extensions in Hayes?
Yes. We build kitchen extensions across Hayes, including postcodes TW8 and TW9. Every project starts with a free home visit.
How much does a kitchen extension cost in Hayes?
In Hayes, 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.
Is underfloor heating worth it?
In a large open-plan space it frees wall space for units and glazing and gives even heat. It is easiest to fit during the build.
Will I need planning permission?
The same rules apply as for any extension. Many single-storey kitchen extensions are permitted development; larger or wraparound designs need an application.
