Neath, Swansea Bay
Semi-detached rear extension in Neath
Thinking about a semi-detached rear extension in Neath? Single or two-storey extensions for semi-detached houses, with side access and one party wall. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
We cover Neath (SA10, SA11 and SA12) as part of our Swansea Bay work. Where a Neath semi already has a small lean-to at the back, we usually replace it rather than extend it.
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 Neath?
In Neath, our guide for a semi-detached rear extension is £1,770–£2,880 per square metre including VAT for a standard specification. 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 |
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 Neath?
Planning for a semi-detached rear extension in Neath follows the Welsh householder rules.
In Wales a single-storey rear extension can often be permitted development if it projects no more than 4 metres beyond the rear wall and is no more than 4 metres high. Wales has no prior approval route for deeper extensions, so anything bigger needs a householder planning application.
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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Neath like to extend?
Older terraces near the centre and post-war semis further out are typical of Neath. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
How a semi-detached rear extension in Neath 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Semi-detached rear extensions near Neath
Neighbouring places we cover include Briton Ferry (2.3 miles) and Clydach (4.3 miles).
- Semi-detached rear extension in Briton Ferry
- Semi-detached rear extension in Clydach
- Semi-detached rear extension in Swansea
- Semi-detached rear extension in Ystalyfera
- Semi-detached rear extension in Maesteg
Other work in Neath:
FAQ
Semi-detached rear extension questions in Neath
What postcode areas do you cover around Neath?
Including SA10, SA11 and SA12, and the surrounding Swansea Bay area.
Do you handle building control in Neath?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
Can I match pebbledash or render?
Yes. Many semis are refinished with new render across the whole back elevation so old and new match.
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 planning permission for a rear extension in Neath?
Often not for a single-storey rear extension of up to 4 metres under Welsh permitted development. Wales has no prior approval route for deeper extensions.
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.