Cobham, Surrey
Kitchen-diner rear extension in Cobham
Thinking about a kitchen-diner rear extension in Cobham? An open-plan kitchen, dining and family room that opens straight onto the garden. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Cobham sits in Surrey, with postcode districts including KT11. A kitchen-diner is often the reason people in Cobham 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 Cobham?
In Cobham, our guide for a kitchen-diner rear extension is £2,130–£3,470 per square metre including VAT for a standard specification. 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 Cobham?
Planning for a kitchen-diner rear extension in Cobham follows the English householder rules.
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. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Cobham like to extend?
Around Cobham 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 Cobham 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 Cobham
Neighbouring places we cover include Esher (3.3 miles) and Weybridge (3.6 miles).
- Kitchen-diner rear extension in Esher
- Kitchen-diner rear extension in Weybridge
- Kitchen-diner rear extension in Great Bookham
- Kitchen-diner rear extension in Walton-on-Thames
- Kitchen-diner rear extension in Leatherhead
Other work in Cobham:
FAQ
Kitchen-diner rear extension questions in Cobham
What postcode areas do you cover around Cobham?
Including KT11, and the surrounding Surrey area.
Is the site visit in Cobham free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Should the sink face the garden?
If the plan allows, an island sink or hob facing the glass is a common choice. It needs a floor-level drain run, which is easy to lay in a new slab.
Do you handle building control in Cobham?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Do I need planning permission for a rear extension in Cobham?
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.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.