West Midlands
Rear extensions for detached houses in the West Midlands
Wider, deeper rear extensions with room for vaulted roofs and big glazing. Across the West Midlands we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Birmingham, Coventry and Wolverhampton.
Detached houses in the West Midlands often have room for a deeper rear extension under England's prior approval route or a full-width design. Red-brick terraces and 1930s semis make up much of the West Midlands. Many already have a small kitchen lean-to at the back, which a new rear extension usually replaces rather than adds to.
How much does a detached house rear extension cost in the West Midlands?
For West Midlands we work from the West Midlands rate: £1,950–£3,200 per square metre of new floor, including VAT, standard specification. The West Midlands is the baseline for our guide prices.
| Size | Guide price inc VAT |
|---|---|
| 4 m wide × 6 m deep (24 m²) | £47,000–£77,000 |
| 5 m wide × 8 m deep (40 m²) | £78,000–£128,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission in the West Midlands?
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.
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.
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.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in the West Midlands do we work?
- Birmingham
- Coventry
- Wolverhampton
- Dudley
- Walsall
- Solihull
- Sutton Coldfield
- West Bromwich
- Halesowen
- Stourbridge
- Smethwick
- Willenhall
- Tipton
- Bloxwich
- Wednesfield
- Washwood Heath
- Aston
- Shirley
- Brierley Hill
- Aldridge
- Acocks Green
- Bartley Green
- Wednesbury
- Kingswinford
- Hockley
- Wombourne
- Brownhills
- Chelmsley Wood
- Streetly
- Pelsall
- Oldbury
- Knowle
- Castle Vale
FAQ
Questions people ask
How deep can I extend a detached house?
4 metres under permitted development in England, or 8 metres with prior approval, outside designated land.
Can I have a vaulted ceiling?
Yes, with a pitched roof and exposed or boxed rafters, subject to the height limits.
Is an oak frame worth it?
It is a premium finish with a long life; it costs more than blockwork with a plain roof.
Do you cover all of the West Midlands?
We cover 33 towns and districts in the West Midlands, including Birmingham, Coventry and Wolverhampton.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.