Chelsfield, Kent
Kitchen-diner rear extension in Chelsfield
Kitchen-diner rear extension in Chelsfield: an open-plan kitchen, dining and family room that opens straight onto the garden. We measure the house, show you what the rules allow, price it in writing and build it.
We cover Chelsfield (BR5 and BR6) as part of our Kent work. A kitchen-diner is often the reason people in Chelsfield extend: the back kitchen in inter-war semis and 1960s estates 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 Chelsfield?
Guide prices for a kitchen-diner rear extension in Chelsfield start from our South East England rate of £2,130–£3,470 per square metre, including VAT. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £25,500–£41,500 |
| 4 m wide × 5 m deep (20 m²) | £42,500–£69,500 |
| 4 m wide × 6 m deep (24 m²) | £51,000–£83,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a kitchen-diner rear extension in Chelsfield?
The planning route for a kitchen-diner rear extension in Chelsfield is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it 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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Chelsfield like to extend?
Around Chelsfield the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.
How a kitchen-diner rear extension in Chelsfield comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
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.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Kitchen-diner rear extensions near Chelsfield
Close by, we work in Orpington, about 1.7 miles away, and Swanley, about 3.3 miles away.
- Kitchen-diner rear extension in Orpington
- Kitchen-diner rear extension in Swanley
- Kitchen-diner rear extension in Bickley
- Kitchen-diner rear extension in Chislehurst
- Kitchen-diner rear extension in Sidcup
Other work in Chelsfield:
FAQ
Kitchen-diner rear extension questions in Chelsfield
Do you handle building control in Chelsfield?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Where does the cooker extraction go?
Through the new wall or roof, ducted to outside. Recirculating hoods are possible but less effective.
Is the site visit in Chelsfield free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Do I need planning permission for a rear extension in Chelsfield?
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.
How long does a rear extension take to build in Chelsfield?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.