Flat roof extensions for homes in Llanelli
Llanelli homeowners can use us for the whole flat roof extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in LlanelliFrom £19,500 inc VAT
- PlanningWelsh permitted development rules (rear up to 4 m)
- Build time10–16 weeks on site
- Postcode districtsSA15
When a flat roof extension makes sense
- Homeowners who want maximum light from above
- Modern and 1930s onwards houses
- Extensions under first-floor windows where a pitch will not fit
Local to Llanelli
Postcode districts we cover around Llanelli include SA15. Neighbouring towns we cover include 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.
How much does a flat roof extension cost in Llanelli?
Labour and material costs vary across the UK, so for Llanelli we use our Wales factor (×0.93). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Llanelli: £1,630 to £3,120 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £19,500 – £23,000 | £22,500 – £29,500 | £29,000 – £37,500 |
| 4 m × 5 m 20 m² | £32,500 – £38,500 | £38,000 – £48,500 | £48,000 – £62,500 |
| 5 m × 6 m 30 m² | £48,500 – £57,500 | £57,000 – £73,000 | £72,500 – £93,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in Llanelli?
In Wales a single-storey rear extension can usually project up to 4 m beyond the rear wall without a planning application, if it is no more than 4 m high, keeps eaves to 3 m and overall height to 4 m within 2 m of a boundary, and covers no more than half the land around the original house. Wales has no larger home extension prior approval scheme.
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).
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Your questions about a flat roof extension in Llanelli
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.
Do I need building regulations approval in Llanelli?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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.
Are flat roof extensions cheaper?
Usually slightly, because there is less roof structure and no tiles. Our guide range is about £1,630 to £3,120 per m² including VAT.
Can I walk on a flat roof extension?
Only for maintenance unless it is designed as a terrace. A roof terrace or balcony needs planning permission and a different structure.
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.