Flat roof extensions across Ashton-under-Lyne
We design and build flat roof extensions for houses in Ashton-under-Lyne, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in Ashton-under-LyneFrom £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 districtsM34, M43, OL6, OL7, SK15
What should I budget for a flat roof extension in Ashton-under-Lyne?
Prices below are for Ashton-under-Lyne, using the North West England factor of ×0.95. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Ashton-under-Lyne: £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.
Will the council need to approve it?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
Who a flat roof extension suits
- Modern and 1930s onwards houses
- Homeowners who want maximum light from above
- Extensions under first-floor windows where a pitch will not fit
Working in Ashton-under-Lyne
Postcode districts we cover around Ashton-under-Lyne include M34, M43, OL6, OL7, SK15, SK16. The same team covers Dukinfield (1 mile), Stalybridge (2 miles), Droylsden (2 miles), Denton (2 miles), all within easy reach.
Wilmslow, in Cheshire, is roughly 12 miles from Ashton-under-Lyne and also on our list. Across the North West, terraced houses with small rear yards suit compact rear and side return extensions, while suburban semis have room for more.
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
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Flat roof extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Ashton-under-Lyne, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a flat roof extension take to build in Ashton-under-Lyne?
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 Ashton-under-Lyne?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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 Ashton-under-Lyne
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.