Weston-super-Mare, Somerset
Semi-detached rear extension in Weston-super-Mare
We plan and build rear extensions for semi-detached houses for homeowners in Weston-super-Mare. 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.
Weston-super-Mare is covered from our Somerset round, including BS22 and BS23. In Weston-super-Mare 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 Weston-super-Mare?
A semi-detached rear extension in Weston-super-Mare is priced at £1,980–£3,220 per square metre including VAT as a guide, before kitchen fit-out and fees. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £23,500–£38,500 |
| 4 m wide × 5 m deep (20 m²) | £39,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £47,500–£77,500 |
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 Weston-super-Mare?
The planning route for a semi-detached rear extension in Weston-super-Mare is set by England's householder rules and your council.
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'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.
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. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Weston-super-Mare like to extend?
Weston-super-Mare has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.
How a semi-detached rear extension in Weston-super-Mare comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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 Weston-super-Mare
Neighbouring places we cover include Yatton (7.2 miles) and Burnham-on-Sea (7.5 miles).
- Semi-detached rear extension in Yatton
- Semi-detached rear extension in Burnham-on-Sea
- Semi-detached rear extension in Clevedon
- Semi-detached rear extension in Penarth
- Semi-detached rear extension in Nailsea
Other work in Weston-super-Mare:
FAQ
Semi-detached rear extension questions in Weston-super-Mare
Do you handle building control in Weston-super-Mare?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
What postcode areas do you cover around Weston-super-Mare?
Including BS22 and BS23, and the surrounding Somerset area.
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.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
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.
Can you match the brick or stone on my Weston-super-Mare house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.