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Hampshire

Rear extensions in Alton

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

Alton is in Hampshire, with postcode districts including GU34. The nearest places we also cover are Bordon (5.5 miles) and Farnham (8.8 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 Alton

Also available across Hampshire:

Rear extension prices in Alton

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 Alton like to extend?

Around Alton 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 Alton

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.

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FAQ

Questions people ask

How much is a rear extension in Alton?

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 Alton?

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 Alton 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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