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Greater London

Rear extensions in Mitcham

We design and build rear extensions for homes in Mitcham, Greater London, from single-storey kitchen-diners across the back of the house to two-storey extensions that add a bedroom above.

Mitcham is in Greater London, with postcode districts including CR4, SM4 and SW17. The nearest places we also cover are Morden (1.3 miles) and Tooting (1.5 miles).

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

Rear extensions we build in Mitcham

Also available across Greater London:

Rear extension prices in Mitcham

London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.

ExampleGuide inc VAT
Single-storey, 3 m × 4 m (12 m²)£29,500–£48,500
Single-storey, 4 m × 6 m (24 m²)£59,500–£96,500
Two-storey, 3 m × 5 m footprint (30 m²)£70,000–£105,500
Side return, about 14 m²£42,000–£69,000
Wraparound, about 25 m²£71,500–£117,000

What are homes in Mitcham like to extend?

Much of Mitcham is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.

Planning rules for Mitcham

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres 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.

Nearby towns

FAQ

Questions people ask

How much is a rear extension in Mitcham?

A 3 m × 4 m single-storey rear extension is about £29,500–£48,500 including VAT at our London guide rates; the written price follows a survey.

Do I need planning permission in Mitcham?

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 Mitcham 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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