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Farnham, Surrey

Single-storey rear extension in Farnham

Single-storey rear extension in Farnham: ground-floor space across the back of the house, usually for a kitchen, dining or family room. We measure the house, show you what the rules allow, price it in writing and build it.

Farnham sits in Surrey, with postcode districts including GU9 and GU10. A depth of 3 to 4 metres keeps many single-storey rear extensions in Farnham within permitted development, subject to the house's planning history.

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 Farnham?

Guide prices for a single-storey rear extension in Farnham start from our South East England rate of £2,130–£3,470 per square metre, including VAT. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.

Single-storey rear extension prices in Farnham
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

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 single-storey rear extension in Farnham?

Whether your single-storey rear extension in Farnham 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 Farnham like to extend?

Farnham has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.

How a single-storey rear extension in Farnham comes together

  1. Look round and measure

    A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.

  2. Options and costs

    We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

  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. 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.

Single-storey rear extensions near Farnham

We also build single-storey rear extensions in nearby Hale (1.2 miles) and Aldershot (2.8 miles).

Other work in Farnham:

All rear extensions in Farnham

FAQ

Single-storey rear extension questions in Farnham

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

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

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.

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.

Do you handle building control in Farnham?

Yes. We apply to the council or a registered building control approver and hand over the completion certificate.

Who will build my extension?

Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.

Can I get a price without a visit?

Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.

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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