Extensions over a garage in Carmarthen: design, approvals and build
Thinking about an over-garage extension for your Carmarthen home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in CarmarthenFrom £22,000 inc VAT
- PlanningAn application to the council is needed
- Build time12–18 weeks on site
- Postcode districtsSA31
Working in Carmarthen
Postcode districts we cover around Carmarthen include SA31. The same team covers Llanelli (13 miles), Ammanford (14 miles), Haverfordwest (29 miles), Pembroke Dock (29 miles), all within easy reach.
In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.
What is included
- Opening into the existing first floor
- Structural survey of garage walls and foundations
- Insulation, electrics, heating and finish
- Strengthening or rebuilding the garage walls if needed
- Design and householder planning application
- New floor structure, walls and roof
Do I need planning permission in Carmarthen?
In Wales a two-storey side extension must be at least 10.5 m from the side boundary to be permitted development, which few houses can meet, so a planning application to the council is the usual route for a room over a garage.
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.
Building over or within 3 m of a public sewer needs the water company's consent before the foundations go in.
Applications are decided by the local planning authority (your county or county borough council, or the national park authority).
What should I budget for an over-garage extension in Carmarthen?
Prices below are for Carmarthen, using the Wales factor of ×0.93. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Carmarthen: £1,670 to £3,160 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £22,000 – £27,500 | £23,000 – £30,500 | £30,000 – £38,000 |
| Over a large single garage 16 m² | £26,500 – £33,000 | £31,000 – £40,500 | £40,000 – £51,000 |
| Over a double garage 24 m² | £40,000 – £49,500 | £46,500 – £60,500 | £60,000 – £76,000 |
For a figure based on your own dimensions, use our guide-price tool.
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Carmarthen
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Carmarthen, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Who do I contract with for an over-garage extension in Carmarthen?
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.
How long does an over-garage extension take to build in Carmarthen?
On site, typically 12 to 18 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
How much does a room over a garage cost?
Our guide range is about £1,670 to £3,160 per m² including VAT. A single-garage room of about 12 m² usually costs £23,000 to £30,500 at standard spec, more if the garage needs rebuilding.
Can I keep using the garage during the build?
Usually not for parking. The garage roof is removed and the space below is used for access and props for part of the build.
Book a free site visit in Carmarthen
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.