Building regulations for extensions across Carmarthen
We prepare building regulations for extensions for homes in Carmarthen, as a stand-alone service or as the first stage of a design and build project.
- Guide price in CarmarthenFrom £800 inc VAT
- Approval routeFull plans or building notice
- Timescale2–5 weeks for drawings
- Postcode districtsSA31
Fees in Carmarthen
Guide fees for Carmarthen including VAT, using our Wales factor of ×0.93. Council and building control charges are not included.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Building regulations drawings for a simple single-storey extension | £800 – £1,700 |
| Standard | Drawings plus structural calculations | £1,200 – £2,450 |
| Premium | Complex or two-storey pack with energy calculations | £2,000 – £3,550 |
Our design fee only. Building control charges are set by your council (or, in England and Wales, a registered building control approver) and quoted separately.Council fees are extra and are set by the Welsh Government.
For a figure based on your own dimensions, use our guide-price tool.
Extensions in and around Carmarthen
Site visits are available across Carmarthen (SA31). Neighbouring towns we cover include Llanelli (13 miles), Ammanford (14 miles), Haverfordwest (29 miles), Pembroke Dock (29 miles).
Gorseinon, in West Glamorgan, is roughly 17 miles from Carmarthen and also on our list. In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.
Planning and approvals in Carmarthen
Building regulations approval is separate from planning. Wales has its own building regulations and approved documents; the council or a registered building control approver checks the plans, inspects the work and issues a completion certificate.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building over or within 3 m of a public sewer needs the water company's consent before the foundations go in.
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 we take care of
- Inspection bookings throughout the build
- Completion certificate on sign-off
- Building regulations drawings and written specification
- Submission to the council or a registered building control approver
- Energy and glazing checks, including whole-house calculations if needed
- Structural calculations for beams, lintels and foundations
Building regulations approval and planning permission are separate. A design can have planning consent and still need changes to meet the regulations, which is why we draw for both together.
How the project works
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
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
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.
How long does this take for a Carmarthen home?
2–5 weeks for drawings, depending on the council and the complexity of the project.
Do I need building regulations approval in Carmarthen?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Full plans or building notice?
A full plans application gets the drawings checked before work starts, which we usually recommend for extensions. A building notice is quicker to submit but carries more risk if something needs changing on site.
Who are building control?
Either your local council’s building control team or a registered building control approver. Both inspect the work and issue the completion certificate.
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.