Two-storey side extensions in Castle Vale

What we'd confirm first for a project in Castle Vale.

Postcode districts: B34, B35, B36 and B76
County / area: West Midlands, England
Price region: West Midlands
Guide price: £86,000–£115,500 (£2,050–£2,750 per m²)
Approval route: Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns: Washwood Heath (1.8 miles), Sutton Coldfield (3.4 miles), Chelmsley Wood (3.7 miles)
Distance to Birmingham: about 5 miles
First visit: Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

We cover Castle Vale (B34, B35, B36 and B76) and the places around it, including Washwood Heath (1.8 miles), Sutton Coldfield (3.4 miles) and Chelmsley Wood.

What it costs in Castle Vale

Guide prices for two-storey side extensions in the West Midlands are around £2,050–£2,750 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £86,000–£115,500. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential	£1,890–£2,530 per m²	£79,000–£106,500
Standard	£2,050–£2,750 per m²	£86,000–£115,500
Premium	£2,460–£3,300 per m²	£103,500–£138,500

Planning and building regulations in Castle Vale

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Castle Vale homes

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

Access and services

Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.

How we'd run your project

Understand the brief
At your home in Castle Vale we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Design and approvals
We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.
Price it properly
Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.
Build and sign-off
Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Questions about two-storey side extensions in Castle Vale

How much does a two-storey side extension cost in Castle Vale?

Our guide for the West Midlands, which covers Castle Vale, is £2,050–£2,750 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £86,000–£115,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Which postcodes do you cover around Castle Vale?

We cover Castle Vale (B34, B35, B36 and B76) and nearby places including Washwood Heath, Sutton Coldfield and Chelmsley Wood, plus the rest of the West Midlands. The first site visit is free.

How long does a two-storey side extension take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Do I need planning permission for a two-storey side extension in Castle Vale?

Castle Vale is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Close to Castle Vale? We work across the area, including:

Other extensions in Castle Vale

All two-storey extension services in Castle Vale · Two-storey side extensions across the West Midlands

Book a free site visit in Castle Vale and we'll tell you what's possible, what approvals you need and what the design stage would cost.