West Midlands
Rear extensions for semi-detached houses in the West Midlands
Single or two-storey extensions for semi-detached houses, with side access and one party wall. Rear extensions in the West Midlands: we cover 33 towns including Birmingham, Coventry and Wolverhampton, with design, approvals and the build under one contract.
Where a Birmingham semi already has a small lean-to at the back, we usually replace it rather than extend it. West Midlands has a lot of post-war semis and estate houses with long gardens and side access, which makes rear extensions quicker to build.
How much does a semi-detached rear extension cost in the West Midlands?
Guide prices for a semi-detached rear extension in the West Midlands start from our West Midlands rate of £1,900–£3,100 per square metre, including VAT. The West Midlands is the baseline for our guide prices.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £23,000–£37,000 |
| 4 m wide × 5 m deep (20 m²) | £38,000–£62,000 |
| 4 m wide × 6 m deep (24 m²) | £45,500–£74,500 |
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?
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.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
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.
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 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.
Can I match pebbledash or render?
Yes. Many semis are refinished with new render across the whole back elevation so old and new match.
Single or two-storey on a semi?
Two-storey if you need bedrooms, single-storey if you need a bigger kitchen. Planning risk is lower for single-storey.
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.