Flat roof extensions in Smethwick: design, approvals and build
If you live in Smethwick 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 SmethwickFrom £20,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsB16, B18, B21, B66, B67
What should I budget for a flat roof extension in Smethwick?
For Smethwick we adjust our national guide rates by ×0.97, the factor we use for West Midlands. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Smethwick: £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 |
For a figure based on your own dimensions, use our guide-price tool.
Working in Smethwick
Across B16, B18, B21, B66, B67, B68, we can visit, measure and advise. The same team covers West Bromwich (2 miles), Birmingham (3 miles), Halesowen (5 miles), Wednesbury (5 miles), all within easy reach.
For homes towards Worcestershire, Bromsgrove is around 12 miles away. The West Midlands has a large stock of 1930s and post-war semi-detached houses, which are well suited to rear, side and over-garage extensions, plus Victorian terraces in the older inner areas.
Do I need planning permission in Smethwick?
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Who a flat roof extension suits
- Homeowners who want maximum light from above
- Extensions under first-floor windows where a pitch will not fit
- Modern and 1930s onwards houses
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 produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Your questions about a flat roof extension in Smethwick
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Smethwick, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Smethwick 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.
How long does a flat roof extension take to build in Smethwick?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
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.
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 Smethwick
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.