House extensions in Alton
Looking to extend your home in Alton? Start here: extension types, guide prices for Alton, the planning rules that apply and how a project runs.
- Postcode districtsGU34
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation
What works best for Alton houses?
The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
Start by comparing single-storey rear extensions, wraparound extensions and orangery extensions: between them they cover most of the layouts we see requested for houses like these.
Areas we cover around Alton
Site visits are available across Alton (GU34). Neighbouring towns we cover include Bordon (5 miles), Basingstoke (9 miles), Fleet (11 miles), Aldershot (11 miles), Farnborough (14 miles). Farnham, in Surrey, is roughly 9 miles from Alton and also on our list.
What extensions cost in Alton
Prices on this page use our South East England factor of ×1.12, include VAT at 20% and cover the build; your written price follows a survey and agreed drawings.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Single-storey rear extensions | 20 m² | £45,500 – £58,500 |
| Conservatory replacement extensions | 14 m² | £33,500 – £43,500 |
| Wraparound extensions | 25 m² | £64,000 – £81,500 |
| Extensions over a garage | 12 m² | £28,000 – £36,500 |
| Side return extensions | 11 m² | £29,500 – £37,000 |
| Orangery extensions | 16 m² | £50,000 – £63,000 |
Do extensions in Alton need planning permission?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
All extension types we build in Alton
- Home office extensions · from £17,500
- Annexe extensions · from £61,500
- Flat roof extensions · from £23,500
- Bedroom extensions · from £29,000
- Utility and boot room extensions · from £15,500
- Double-storey extensions · from £42,500
- Bungalow extensions · from £29,000
- Orangery extensions · from £33,500
- Timber frame extensions · from £23,500
- Conservatory replacement extensions · from £22,000
- Kitchen extensions · from £30,000
- Planning permission for extensions · from £350
- Building regulations for extensions · from £1,000
- Wraparound extensions · from £40,000
- Porch extensions · from £4,450
- Extension plans and drawings · from £1,300
- Extensions over a garage · from £26,500
- Pitched roof extensions · from £24,500
- Glass box extensions · from £33,500
- Side return extensions · from £20,000
- Single-storey rear extensions · from £23,500
- Side extensions · from £24,500
Free site visit
We visit your Alton home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions about extensions in Alton
How much does an extension cost in Alton?
Using our South East England factor (×1.12), a standard-spec single-storey extension of 20 m² is a guide £45,500 to £58,500 including VAT, and a 32 m² two-storey extension £64,500 to £84,500. Your written price follows the survey.
Do I need planning permission for an extension in Alton?
Not always. It depends on the size, position and your property's history. Many single-storey rear extensions in England are permitted development or can use prior approval.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
How long does an extension take in Alton?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Alton, and the guide-price tool gives a range for your own size and finish in about a minute.
Book a free site visit in Alton
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.