Streetly, West Midlands
Semi-detached rear extension in Streetly
We plan and build rear extensions for semi-detached houses for homeowners in Streetly. Single or two-storey extensions for semi-detached houses, with side access and one party wall. Start with a free site visit, then a written price once the design is agreed.
Streetly is covered from our West Midlands round, including B44, B73 and B74. In Streetly we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours.
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 Streetly?
Guide prices for a semi-detached rear extension in Streetly 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 |
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 Streetly?
Here is how the rules in England apply to a semi-detached rear extension in Streetly.
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.
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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Streetly like to extend?
Streetly has a lot of post-war semis and estate houses with long gardens and side access, which makes rear extensions quicker to build.
How a semi-detached rear extension in Streetly comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Semi-detached rear extensions near Streetly
Neighbouring places we cover include Aldridge (2.1 miles) and Sutton Coldfield (3.0 miles).
- Semi-detached rear extension in Aldridge
- Semi-detached rear extension in Sutton Coldfield
- Semi-detached rear extension in Brownhills
- Semi-detached rear extension in Walsall
- Semi-detached rear extension in Pelsall
Other work in Streetly:
FAQ
Semi-detached rear extension questions in Streetly
What postcode areas do you cover around Streetly?
Including B44, B73 and B74, and the surrounding West Midlands area.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Do I need a party wall agreement?
Usually with the attached neighbour, in England and Wales.
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.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Do you handle building control in Streetly?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.