Side extensions in Cowbridge: design, approvals and build
A side extension in Cowbridge starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in CowbridgeFrom £20,000 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsCF71
Included in a typical project
- New openings through the side wall
- Windows, doors and finishes to match
- Foundations near boundaries and any drains
- Structure, roof tied into the house
- Planning route checked or application made
Covering Cowbridge
We cover Cowbridge and the postcode districts CF71. The same team covers Barry (8 miles), Cardiff (12 miles), Penarth (12 miles), all within easy reach.
Welsh housing ranges from stone terraces in the valleys to render-and-slate houses and modern estates, and the Welsh planning rules differ from England's in several places.
Guide prices for Cowbridge
These guide figures apply our Wales adjustment (×0.93) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Cowbridge: £1,630 to £3,160 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £20,000 – £25,000 | £22,500 – £30,000 | £29,000 – £38,000 |
| 3 m × 6 m 18 m² | £29,000 – £35,500 | £34,000 – £44,500 | £43,500 – £57,000 |
| 3 m × 8 m 24 m² | £39,000 – £47,000 | £45,500 – £59,500 | £58,000 – £76,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Will the council need to approve it?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
What happens next
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
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
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Side extension questions answered
Will my neighbours in Cowbridge be involved?
If a planning application is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Who do I contract with for a side extension in Cowbridge?
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.
Do you cover all of Cowbridge?
Yes. We cover Cowbridge and the surrounding parts of South Glamorgan. Site visits are free and there is no obligation.
Can I build over my driveway?
Yes, if the foundations work and you keep any parking the council requires. Drains and services under drives are common, so we check before design.
How much does a side extension cost?
Our guide range is about £1,630 to £3,160 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £34,000 to £44,500 in Cowbridge.
Book a free site visit in Cowbridge
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.