Double-storey extensions in Llanelli
We design and build double-storey extensions for houses in Llanelli, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in LlanelliFrom £35,000 inc VAT
- PlanningUsually a planning application
- Build time16–24 weeks on site
- Postcode districtsSA15
How much does a double-storey extension cost in Llanelli?
Prices below are for Llanelli, using the Wales factor of ×0.93. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Llanelli: £1,440 to £2,790 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £35,000 – £42,500 | £40,000 – £52,500 | £51,000 – £67,000 |
| 4 m × 4 m, two floors 32 m² | £46,000 – £55,500 | £53,500 – £70,000 | £68,000 – £89,500 |
| 4 m × 6 m, two floors 48 m² | £69,000 – £83,000 | £80,000 – £105,000 | £102,500 – £134,000 |
Try the guide-price tool to see a range for your own size and finish.
When a double-storey extension makes sense
- Houses with enough distance to the rear or side boundary
- Growing families who need a bedroom as well as a bigger kitchen
- Homeowners who would otherwise consider moving
Local to Llanelli
Our survey diary covers Llanelli, including SA15. The same team covers Ammanford (11 miles), Carmarthen (13 miles), Pembroke Dock (33 miles), Haverfordwest (36 miles), all within easy reach.
Just over the West Glamorgan border, Gorseinon is about 5 miles away. 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.
Planning rules that apply in Llanelli
In Wales a rear extension of more than one storey can be permitted development only if the ground floor projects no more than 4 m, the upper floor no more than 3 m, it stays at least 10.5 m from the rear boundary and it is not in a conservation area, national park, National Landscape or World Heritage Site. Anything larger needs a planning application to the council.
The planning position for a specific Llanelli address depends on its history and any designations, which is why we check it at the first visit.
Building over or within 3 m of a public sewer needs the water company's consent before the foundations go in.
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.
Applications are decided by the local planning authority (your county or county borough council, or the national park authority).
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
We visit your Llanelli home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Llanelli
How long does a double-storey extension take to build in Llanelli?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
Who do I contract with for a double-storey 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.
Do you cover all of Llanelli?
Yes. We cover Llanelli and the surrounding parts of Dyfed. Site visits are free and there is no obligation.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,440 to £2,790 per m² of new floor area including VAT, compared with £1,630 to £3,160 per m² for single-storey work, because the foundations and roof are shared across two floors.
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.