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 St Helens?
In St Helens, a kitchen extension typically costs £2,100–£3,200 per m² including a mid-range kitchen, including VAT at 20% (standard rate). For a typical 22 m² project that is roughly £46,000–£70,500. That range is adjusted for the North West, where domestic building work typically costs around 6% below the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (15 m²) | £31,500–£48,000 |
| Typical project (22 m²) | £46,000–£70,500 |
| Larger project (31 m²) | £65,000–£99,000 |
| Rate per m² | £2,100–£3,200 |
What moves the price most:
- Island with sink or hob, which needs services in the floor
- Underfloor heating and flooring
- Who supplies the kitchen
- Extension size and roof design
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a kitchen extension in St Helens?
Approvals for a kitchen extension in St Helens follow the rules for 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
Handled as part of most kitchen extensions:
- Building control sign-off
- Electrics, lighting plan and sockets
- Kitchen layout planned alongside the extension design
- Kitchen fitting, worktops and splashbacks
- Drainage and water supply positioned for the sink and appliances
- Extension structure, roof and glazing
How long does it take?
Allow 11 to 16 weeks on site, including kitchen fitting. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in St Helens
Terraced streets across the North West often suit rear dormers and single-storey kitchen extensions.
From WA10 outwards, we take on projects throughout St Helens and the surrounding parts of Merseyside.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about kitchen extensions in St Helens
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.
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.
How much does a kitchen extension cost in St Helens?
In St Helens, a kitchen extension typically costs £2,100–£3,200 per m² including a mid-range kitchen, including VAT at 20% (standard rate). A typical 22 m² project comes to roughly £46,000–£70,500. Your fixed price depends on the survey and drawings.
Do you build kitchen extensions in St Helens?
Yes. We build kitchen extensions across St Helens, including postcodes WA10. Every project starts with a free home visit.
How long will I be without a kitchen?
Usually 3 to 6 weeks at the end of the job, once the back wall is opened and the new kitchen goes in. We can help set up a temporary kitchen.