Stourbridge · West Midlands

Extensions over a garage in Stourbridge

Thinking about an extension over a garage in Stourbridge? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

Before you start in Stourbridge, here's what applies.

Postcode districts
DY8 and DY9
County / area
West Midlands, England
Price region
West Midlands
Guide price
£31,500–£46,000 (£1,750–£2,550 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Brierley Hill (2 miles), Kingswinford (3.1 miles), Dudley (3.9 miles)
Distance to Birmingham
about 10.4 miles
First visit
Free, no obligation

About an extension over a garage

An extension over a garage is a new first-floor room built on top of an existing attached garage, usually a bedroom, en-suite or study. It uses a footprint you already have, so it adds floor space without taking any garden. The garage walls and foundations often need strengthening or replacing to carry the new floor.

We cover Stourbridge (DY8 and DY9) and the places around it, including Brierley Hill (2.0 miles), Kingswinford (3.1 miles) and Dudley.

What it costs in Stourbridge

In the West Midlands, which includes Stourbridge, we'd expect an extension over a garage to cost around £31,500–£46,000 for 3 m × 6 m of new first-floor space (18 m²), or £1,750–£2,550 per m² including VAT. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²3 m × 6 m of new first-floor space (18 m²)
Essential£1,610–£2,350 per m²£29,000–£42,000
Standard£1,750–£2,550 per m²£31,500–£46,000
Premium£2,100–£3,060 per m²£38,000–£55,000

Planning and building regulations in Stourbridge

In England, most garages sit beside the house, so building over one makes a two-storey extension beyond a side wall, which always needs planning permission. If the garage is at the rear, the 3 m and 7 m rules for two-storey rear extensions apply, measured from the original house. A householder application costs £548 (or £575 for applications made from 8 December 2026).

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 Stourbridge homes

Checking the garage foundations

Garages are often built on shallow strip footings sized for a single-storey wall and a light roof. A trial hole shows their depth and condition, and the engineer decides whether they can carry two storeys or need underpinning or new foundations inside the garage.

Fire separation

If the garage stays a garage, the floor between it and the room above, and any door into the house, must give fire separation under building regulations. That usually means fire-resisting plasterboard ceilings, sealed gaps and a fire door, which we design in from the start.

How we'd run your project

  1. Look at the house

    We start in Stourbridge with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Stourbridge.

  3. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about extensions over a garage in Stourbridge

Do I need planning permission for an extension over a garage in Stourbridge?

Stourbridge 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.

How long does an extension over a garage 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.

Which postcodes do you cover around Stourbridge?

We cover Stourbridge (DY8 and DY9) and nearby places including Brierley Hill, Kingswinford and Dudley, plus the rest of the West Midlands. The first site visit is free.

Do I need to convert the garage as well?

No. You can keep the garage for parking or storage and build only the room above, as long as the floor between them and any door into the house meet fire separation rules. Converting the garage at the same time is often good value, because the walls and foundations may be upgraded anyway.

Can I add an en-suite above the garage?

Yes, and it is a common choice for a main bedroom. The en-suite needs an extract fan under Part F, a route for the soil pipe down to the drains and enough fall for the waste, which can be harder over a garage. We plan the pipe route through the garage or an outside wall early.

Nearby

We also cover places near Stourbridge, including:

Other extensions in Stourbridge

All two-storey extension services in Stourbridge · Extensions over a garage across the West Midlands

The quickest next step is a visit. We'll look at your house in Stourbridge and give you an honest view of the options.

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