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Surrey

Rear extensions in Cobham

From the first measured visit to building control sign-off, we handle rear extensions in Cobham under one contract.

Cobham is in Surrey, with postcode districts including KT11. The nearest places we also cover are Esher (3.3 miles) and Weybridge (3.6 miles).

Book a free site visit

Tell us about the house and we'll call to arrange a free, no-obligation visit.

Rear extensions we build in Cobham

Also available across Surrey:

Rear extension prices in Cobham

South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.

ExampleGuide inc VAT
Single-storey, 3 m × 4 m (12 m²)£25,500–£41,500
Single-storey, 4 m × 6 m (24 m²)£51,000–£83,500
Two-storey, 3 m × 5 m footprint (30 m²)£60,500–£90,500
Side return, about 14 m²£36,000–£59,500
Wraparound, about 25 m²£61,500–£101,000

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.

Planning rules for Cobham

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.

Planning and Building Regulations are separate in England: even a permitted development extension is inspected for foundations, drainage, structure, insulation, fire safety and ventilation, through the council or a registered building control approver, ending with a completion certificate.

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FAQ

Questions people ask

How much is a rear extension in Cobham?

A 3 m × 4 m single-storey rear extension is about £25,500–£41,500 including VAT at our South East England guide rates; the written price follows a survey.

Do I need planning permission 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.

Is the site visit in Cobham free?

Yes, with no obligation.

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.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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