Annexe extensions in Llanelli: design, approvals and build
Our design and build teams take on annexe extensions in Llanelli, from the first measured survey through planning and building control to the finished room.
- Guide price in LlanelliFrom £51,000 inc VAT
- PlanningUsually a planning application
- Build time16–24 weeks on site
- Postcode districtsSA15
How much does an annexe extension cost in Llanelli?
For Llanelli we adjust our national guide rates by ×0.93, the factor we use for Wales. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Llanelli: £1,860 to £3,530 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £51,000 – £64,000 | £55,500 – £70,000 | £69,500 – £88,500 |
| One-bedroom annexe 35 m² | £65,000 – £81,500 | £78,000 – £98,000 | £97,500 – £124,000 |
| Larger annexe 45 m² | £83,500 – £105,000 | £100,000 – £126,000 | £125,500 – £159,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Planning rules that apply in Llanelli
In Wales an annexe linked to the house and used by your household is assessed as an extension, but its size usually means a planning application is needed.
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.
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 we take care of
- Design for accessibility: level thresholds, wider doors, walk-in shower
- Planning application describing ancillary use
- Separate or shared heating and hot water
- Fire separation and alarms to building regulations
- Kitchenette, shower room and bedroom finish
Extensions in and around Llanelli
We cover Llanelli and the postcode districts SA15. Nearby, we also take on projects in Ammanford (11 miles), Carmarthen (13 miles), Pembroke Dock (33 miles), Haverfordwest (36 miles).
Gorseinon, in West Glamorgan, is roughly 5 miles from Llanelli 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.
Our process, step by step
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
We visit your Llanelli home, measure up, talk through what you want and check the planning position.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Questions people ask about annexe extensions
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Llanelli, 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 annexe extension in Llanelli?
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 in Llanelli 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.
Does an annexe extension need planning permission?
Usually yes, because of its size and the way it will be used. Councils check that it stays ancillary to the main house, so the application must describe the use clearly.
Will an annexe affect council tax?
It can. Some annexes are assessed separately for council tax, with discounts or exemptions in some cases when occupied by a relative. Check with the Valuation Office Agency (England and Wales), your local assessor (Scotland) or Land & Property Services (Northern Ireland).
Book a free site visit in Llanelli
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.