Barnham, West Sussex
Kitchen-diner rear extension in Barnham
We plan and build kitchen-diner rear extensions for homeowners in Barnham. An open-plan kitchen, dining and family room that opens straight onto the garden. Start with a free site visit, then a written price once the design is agreed.
Barnham and its postcode districts BN18 and PO22 are part of our West Sussex coverage. For Barnham kitchens we plan the extraction route and the island drainage before the slab is poured, so nothing has to be chased in later.
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 Barnham?
A kitchen-diner rear extension in Barnham is priced at £2,130–£3,470 per square metre including VAT as a guide, before kitchen fit-out and fees. 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 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a kitchen-diner rear extension in Barnham?
Whether your kitchen-diner rear extension in Barnham needs a planning application depends on its size, your house and any local restrictions.
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. 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 Barnham like to extend?
Commuter semis and detached houses make up much of Barnham, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a kitchen-diner rear extension in Barnham 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.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Kitchen-diner rear extensions near Barnham
We also build kitchen-diner rear extensions in nearby Bognor Regis (3.9 miles) and Littlehampton (4.5 miles).
- Kitchen-diner rear extension in Bognor Regis
- Kitchen-diner rear extension in Littlehampton
- Kitchen-diner rear extension in Rustington
- Kitchen-diner rear extension in Chichester
- Kitchen-diner rear extension in Selsey
Other work in Barnham:
FAQ
Kitchen-diner rear extension questions in Barnham
How long does a rear extension take to build in Barnham?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do you handle building control in Barnham?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Do you fit the kitchen?
Yes, whether you buy it yourself or we supply it. We take the measurements from the built shell, not the drawings.
Do I need planning permission for a rear extension in Barnham?
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.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
What postcode areas do you cover around Barnham?
Including BN18 and PO22, and the surrounding West Sussex area.