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Slough, Berkshire

Single-storey rear extension in Slough

Thinking about a single-storey rear extension in Slough? Ground-floor space across the back of the house, usually for a kitchen, dining or family room. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.

We cover Slough (SL1, SL2 and SL3) as part of our Berkshire work. A single-storey rear extension in Slough is mostly built from the garden side, so the house stays usable for most of the job.

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 single-storey rear extension cost in Slough?

A single-storey rear extension in Slough 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.

Single-storey rear extension prices in Slough
SizeGuide 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 single-storey rear extension in Slough?

Whether your single-storey rear extension in Slough needs a planning application depends on its size, your house and any local restrictions.

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.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

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 Slough like to extend?

Commuter semis and detached houses make up much of Slough, and longer gardens make England's prior approval route for deeper rear extensions worth considering.

How a single-storey rear extension in Slough comes together

  1. 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.

  2. Drawings and budget

    Floor plans and elevations for the options, each with a guide price.

  3. Approvals

    Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.

  4. 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.

Single-storey rear extensions near Slough

Close by, we work in Windsor, about 1.8 miles away, and Burnham, about 3.5 miles away.

Other work in Slough:

All rear extensions in Slough

FAQ

Single-storey rear extension questions in Slough

Can you match the brick or stone on my Slough house?

We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.

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.

How deep can a single-storey rear extension be without planning?

In England, 3 metres on an attached house and 4 metres on a detached house under permitted development, or up to 6 and 8 metres with prior approval. Wales allows 4 metres; Scotland and Northern Ireland have their own limits.

How long does a rear extension take to build in Slough?

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 I need planning permission for a rear extension in Slough?

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.

Will I need a structural engineer?

Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.

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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