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Fair Oak, Hampshire

Semi-detached rear extension in Fair Oak

For homes in Fair Oak, a semi-detached rear extension is often the simplest way to gain space without moving. Single or two-storey extensions for semi-detached houses, with side access and one party wall. We take it from survey to completion certificate.

Fair Oak is covered from our Hampshire round, including SO30, SO50 and SO53. Semi-detached houses are common across Hampshire, and their side access makes rear extensions quicker to build.

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 semi-detached rear extension cost in Fair Oak?

In Fair Oak, our guide for a semi-detached 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.

Semi-detached rear extension prices in Fair Oak
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 semi-detached rear extension in Fair Oak?

Whether your semi-detached rear extension in Fair Oak needs a planning application depends on its size, your house and any local restrictions.

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.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.

What are homes in Fair Oak like to extend?

Around Fair Oak 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 semi-detached rear extension in Fair Oak 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. Design and guide price

    Two or three layout options with a guide price for each, so you choose the design knowing what it costs.

  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. Build and sign-off

    We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.

Semi-detached rear extensions near Fair Oak

We also build rear extensions for semi-detached houses in nearby Bishopstoke (1.4 miles) and Eastleigh (2.3 miles).

Other work in Fair Oak:

All rear extensions in Fair Oak

FAQ

Semi-detached rear extension questions in Fair Oak

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.

Do I need planning permission for a rear extension in Fair Oak?

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.

How far can I extend a semi without planning?

3 metres under permitted development in England, or up to 6 metres with prior approval, outside designated land.

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.

Do you handle building control in Fair Oak?

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

Can you match the brick or stone on my Fair Oak house?

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

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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