Briton Ferry, Swansea Bay
Semi-detached rear extension in Briton Ferry
Single or two-storey extensions for semi-detached houses, with side access and one party wall. If you live in Briton Ferry and want to know what a semi-detached rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Briton Ferry sits in Swansea Bay, with postcode districts including SA10, SA11 and SA12. Semi-detached houses are common across Swansea Bay, and their side access makes rear extensions quicker to build.
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 Briton Ferry?
A semi-detached rear extension in Briton Ferry is priced at £1,770–£2,880 per square metre including VAT as a guide, before kitchen fit-out and fees. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,000–£34,500 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£57,500 |
| 4 m wide × 6 m deep (24 m²) | £42,500–£69,000 |
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 for a semi-detached rear extension in Briton Ferry?
Here is how the rules in Wales apply to a semi-detached rear extension in Briton Ferry.
The Welsh Government's householder rules let many homes add a single-storey rear extension up to 4 metres deep and 4 metres high without a planning application. Deeper projects go through a householder application, because Wales has no prior approval route.
Welsh rules allow a two-storey rear extension without an application only where the ground floor is no deeper than 4 metres, the upper floor no deeper than 3 metres and at least 10.5 metres remains to the rear boundary. Most homeowners still apply for householder planning permission.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development or a householder planning application.
What are homes in Briton Ferry like to extend?
Older terraces near the centre and post-war semis further out are typical of Briton Ferry. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
How a semi-detached rear extension in Briton Ferry 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.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Paperwork handled
Planning 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 Briton Ferry
Close by, we work in Neath, about 2.3 miles away, and Clydach, about 5.0 miles away.
- Semi-detached rear extension in Neath
- Semi-detached rear extension in Clydach
- Semi-detached rear extension in Swansea
- Semi-detached rear extension in Maesteg
- Semi-detached rear extension in Pyle
Other work in Briton Ferry:
FAQ
Semi-detached rear extension questions in Briton Ferry
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.
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.
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.
How long does a rear extension take to build in Briton Ferry?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
What postcode areas do you cover around Briton Ferry?
Including SA10, SA11 and SA12, and the surrounding Swansea Bay area.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.