Chelsea, Greater London
Kitchen-diner rear extension in Chelsea
An open-plan kitchen, dining and family room that opens straight onto the garden. We design, get the approvals for and build kitchen-diner rear extensions in Chelsea and the surrounding area, with one contract from the first survey to building control sign-off.
We cover Chelsea (SW3, SW7 and SW10) as part of our Greater London work. A kitchen-diner is often the reason people in Chelsea extend: the back kitchen in period terraces and mansion flats is rarely big enough for a table.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a kitchen-diner rear extension cost in Chelsea?
In Chelsea, our guide for a kitchen-diner rear extension is £2,470–£4,030 per square metre including VAT for a standard specification. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £29,500–£48,500 |
| 4 m wide × 5 m deep (20 m²) | £49,500–£80,500 |
| 4 m wide × 6 m deep (24 m²) | £59,500–£96,500 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a kitchen-diner rear extension in Chelsea?
Whether your kitchen-diner rear extension in Chelsea needs a planning application depends on its size, your house and any local restrictions.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Chelsea like to extend?
Period terraces in Chelsea sit alongside flats, and the difference matters: houses usually keep permitted development rights, while flats and maisonettes need planning permission for any rear extension.
How a kitchen-diner rear extension in Chelsea comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Kitchen-diner rear extensions near Chelsea
We also build kitchen-diner rear extensions in nearby Battersea (1.1 miles) and Fulham (1.4 miles).
- Kitchen-diner rear extension in Battersea
- Kitchen-diner rear extension in Fulham
- Kitchen-diner rear extension in Pimlico
- Kitchen-diner rear extension in Notting Hill
- Kitchen-diner rear extension in Shepherds Bush
Other work in Chelsea:
FAQ
Kitchen-diner rear extension questions in Chelsea
How long does a rear extension take to build in Chelsea?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Can I have underfloor heating?
Yes. Wet underfloor heating in the new screed is the usual choice, often with the old room's radiators kept or replaced.
Do I need planning permission for a rear extension in Chelsea?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Is the site visit in Chelsea free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.