Flat roof extensions across West Midlands
A flat roof extension in West Midlands starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide priceFrom £20,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Towns covered20
- Site visitFree, no obligation

Towns in West Midlands
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.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
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 should I budget for a flat roof extension in West Midlands?
Prices below are for West Midlands, using the West Midlands factor of ×0.97. They are guide ranges including VAT for the build only, not a quote.
Typical rates in West Midlands: £1,700 to £3,250 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £20,000 – £24,000 | £23,500 – £30,500 | £30,000 – £39,000 |
| 4 m × 5 m 20 m² | £33,500 – £40,000 | £39,500 – £50,500 | £50,000 – £65,000 |
| 5 m × 6 m 30 m² | £50,500 – £60,000 | £59,500 – £76,000 | £75,500 – £97,500 |
Try the guide-price tool to see a range for your own size and finish.
Local to West Midlands
Towns we cover in West Midlands include Birmingham, Coventry, Wolverhampton, Dudley, Walsall, Solihull, Sutton Coldfield, West Bromwich. Across the West Midlands, brick-built semis with long gardens are common, so single-storey and two-storey rear extensions are popular choices.
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
From first visit to completion
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
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Questions people ask about flat roof extensions
Do I need building regulations approval in West Midlands?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a flat roof extension take to build in West Midlands?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Will my neighbours in West Midlands be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
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 £1,700 to £3,250 per m² including VAT.
Book a free site visit in West Midlands
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.