Double-storey extensions for homes in West Bromwich
Thinking about a double-storey extension for your West Bromwich home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in West BromwichFrom £36,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsB21, B66, B67, B69, B70

Included in a typical project
- Insulation, plastering, electrics and plumbing to finish
- Ground and first floor structure, roof tied into the existing roof
- Breaking through at both levels, stairs and landing changes where needed
- Measured survey, design and planning drawings
- Householder planning application where needed
- Foundations sized for two floors
Working in West Bromwich
Our survey diary covers West Bromwich, including B21, B66, B67, B69, B70, B71. We also work in nearby Smethwick (2 miles), Wednesbury (3 miles), Tipton (3 miles), Dudley (4 miles).
Just over the Staffordshire border, Great Wyrley is about 10 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.
What should I budget for a double-storey extension in West Bromwich?
Labour and material costs vary across the UK, so for West Bromwich we use our West Midlands factor (×0.97). The ranges include VAT and exclude design, structural and council fees.
Typical rates in West Bromwich: £1,500 to £2,910 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £36,500 – £44,000 | £41,500 – £55,000 | £53,500 – £70,000 |
| 4 m × 4 m, two floors 32 m² | £48,000 – £57,500 | £55,500 – £73,000 | £71,000 – £93,500 |
| 4 m × 6 m, two floors 48 m² | £72,000 – £86,500 | £83,500 – £109,500 | £107,000 – £140,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in West Bromwich?
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
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.
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).
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Double-storey extension questions answered
Do you cover all of West Bromwich?
Yes. We cover West Bromwich and the surrounding parts of West Midlands. Site visits are free and there is no obligation.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for West Bromwich, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in West Bromwich?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Book a free site visit in West Bromwich
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.