Flat roof extensions for homes in Mid Glamorgan
If you live in Mid Glamorgan and want more space without moving, a flat roof extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide priceFrom £19,500 inc VAT
- PlanningWelsh permitted development rules (rear up to 4 m)
- Towns covered12
- Site visitFree, no obligation
Towns in Mid Glamorgan
Local to Mid Glamorgan
Towns we cover in Mid Glamorgan include Rhondda, Tonypandy, Bridgend, Merthyr Tydfil, Pontypridd, Aberdare, Caerphilly, Maesteg. In Wales, terraced houses with rear offshoots are common in the towns, while detached houses and bungalows dominate in rural areas.
When a flat roof extension makes sense
- Modern and 1930s onwards houses
- Extensions under first-floor windows where a pitch will not fit
- Homeowners who want maximum light from above
Flat roof extension prices in Mid Glamorgan
These guide figures apply our Wales adjustment (×0.93) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Mid Glamorgan: £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.
Planning rules that apply in Mid Glamorgan
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.
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 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 Mid Glamorgan 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
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 flat roof extensions
How long does a flat roof extension take to build in Mid Glamorgan?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Do I need building regulations approval in Mid Glamorgan?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Mid Glamorgan?
Yes, across the whole of Mid Glamorgan. Site visits are free and there is no obligation.
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.
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.
Book a free site visit in Mid Glamorgan
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.