House extensions in Swansea
Planning an extension in Swansea? Compare extension types, see guide prices adjusted for Swansea and book a free site visit.
- Postcode districtsSA1, SA2, SA3, SA5, SA6, SA7
- Price regionWales (×0.93)
- Planning rulesWales
- Site visitFree, no obligation
Which extension suits a Swansea home?
In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.
Start by comparing single-storey rear extensions, bungalow extensions and side return extensions: between them they cover most of the layouts we see requested for houses like these.
What extensions cost in Swansea
We publish guide prices so you can budget before anyone visits. For Swansea they are adjusted by ×0.93, the factor we use across Wales.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Single-storey rear extensions | 20 m² | £38,000 – £48,500 |
| Side return extensions | 11 m² | £24,500 – £31,000 |
| Wraparound extensions | 25 m² | £53,000 – £67,500 |
| Extensions over a garage | 12 m² | £23,000 – £30,500 |
| Orangery extensions | 16 m² | £41,500 – £52,500 |
| Kitchen extensions | 20 m² | £39,000 – £49,500 |
Do extensions in Swansea need planning permission?
In Wales a single-storey rear extension can usually project up to 4 m beyond the rear wall without a planning application, if it is no more than 4 m high, keeps eaves to 3 m and overall height to 4 m within 2 m of a boundary, and covers no more than half the land around the original house. Wales has no larger home extension prior approval scheme.
In Wales a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house, and it must not come closer to a highway than the existing side wall. Larger side extensions need planning permission.
In a conservation area, national park, National Landscape or World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
The Party Wall etc. Act 1996 applies in Wales as in England: notice must be served before work to a shared wall, building on the boundary, or excavating close to a neighbour's foundations.
Applications are decided by the local planning authority (your county or county borough council, or the national park authority).
Where we work near Swansea
Postcode districts we cover around Swansea include SA1, SA2, SA3, SA5, SA6, SA7. We also work in nearby Clydach (5 miles), Briton Ferry (5 miles), Gorseinon (5 miles), Neath (7 miles). Llanelli, in Dyfed, is roughly 10 miles from Swansea and also on our list.
Every extension type in Swansea
- Planning permission for extensions · from £300
- Utility and boot room extensions · from £13,000
- Double-storey extensions · from £35,000
- Side return extensions · from £16,500
- Single-storey rear extensions · from £19,500
- Building regulations for extensions · from £800
- Conservatory replacement extensions · from £18,500
- Home office extensions · from £14,500
- Flat roof extensions · from £19,500
- Extension plans and drawings · from £1,100
- Glass box extensions · from £27,500
- Extensions over a garage · from £22,000
- Side extensions · from £20,000
- Pitched roof extensions · from £20,500
- Annexe extensions · from £51,000
- Kitchen extensions · from £25,000
- Timber frame extensions · from £19,500
- Orangery extensions · from £27,500
- Wraparound extensions · from £33,000
- Bungalow extensions · from £24,000
- Bedroom extensions · from £24,000
- Porch extensions · from £3,700
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Swansea
How much does an extension cost in Swansea?
Using our Wales factor (×0.93), a standard-spec single-storey extension of 20 m² is a guide £38,000 to £48,500 including VAT, and a 32 m² two-storey extension £53,500 to £70,000. Your written price follows the survey.
Who do I contract with?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Will my neighbours need to be told?
If you apply for planning the council notifies them, and in Wales party wall notices may be needed for work near a shared boundary.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Swansea, and the guide-price tool gives a range for your own size and finish in about a minute.
Book a free site visit in Swansea
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.