Flat roof extensions across Thornton-Cleveleys
If you live in Thornton-Cleveleys 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 price in Thornton-CleveleysFrom £19,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsFY2, FY5, FY6
How much does a flat roof extension cost in Thornton-Cleveleys?
For Thornton-Cleveleys we adjust our national guide rates by ×0.95, the factor we use for North West England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Thornton-Cleveleys: £1,660 to £3,180 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £19,500 – £23,500 | £23,000 – £30,000 | £29,500 – £38,500 |
| 4 m × 5 m 20 m² | £33,000 – £39,000 | £38,500 – £49,500 | £49,000 – £64,000 |
| 5 m × 6 m 30 m² | £49,500 – £58,500 | £58,000 – £74,500 | £74,000 – £95,500 |
For a figure based on your own dimensions, use our guide-price tool.
Working in Thornton-Cleveleys
Our survey diary covers Thornton-Cleveleys, including FY2, FY5, FY6. Nearby, we also take on projects in Poulton-le-Fylde (3 miles), Fleetwood (4 miles), Blackpool (4 miles), Lytham St Annes (9 miles).
Southport, in Merseyside, is roughly 16 miles from Thornton-Cleveleys and also on our list. The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
What we take care of
- Lanterns or rooflights with upstands
- Membrane choice: single-ply, EPDM or GRP
- Warm-roof design with insulation above the deck
- Falls and outlets designed to drain properly
Planning rules that apply in Thornton-Cleveleys
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
The planning position for a specific Thornton-Cleveleys address depends on its history and any designations, which is why we check it at the first visit.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
What happens next
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
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Flat roof extension questions answered
Do you cover all of Thornton-Cleveleys?
Yes. We cover Thornton-Cleveleys and the surrounding parts of Lancashire. Site visits are free and there is no obligation.
Who do I contract with for a flat roof extension in Thornton-Cleveleys?
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.
How long does a flat roof extension take to build in Thornton-Cleveleys?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
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 £1,660 to £3,180 per m² including VAT.
Book a free site visit in Thornton-Cleveleys
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.