Extensions over a garage in Aston

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

Postcode districts: B6 and B7
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: Hockley (1.4 miles), Birmingham (1.5 miles), Washwood Heath (2.4 miles)
Distance to Birmingham: about 1.5 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 Aston (B6 and B7) and the places around it, including Hockley (1.4 miles), Birmingham (1.5 miles) and Washwood Heath.

What it costs in Aston

For budgeting in Aston, allow around £31,500–£46,000 for an extension over a garage with 3 m × 6 m of new first-floor space (18 m²). That's based on £1,750–£2,550 per m² including VAT for the West Midlands. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

Spec	Per m²	3 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 Aston

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 Aston homes

Floor levels and headroom

Garage floors are often lower than the house, and the new first floor may not line up with the existing landing. We set the floor level to avoid awkward steps upstairs, while keeping enough headroom in the garage below for a car or storage.

Garage walls and the door opening

Garage walls are often a single skin of brick or block with piers, and the wide door opening needs a beam over it. Many over-garage extensions need new inner walls or a steel frame to carry the floor and to insulate properly, which we confirm before the design is fixed.

How we'd run your project

Look at the house
We start in Aston with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about extensions over a garage in Aston

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

Aston 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.

Who handles building regulations for a project in Aston?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

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.

How do I get into a room over the garage?

Usually through a new opening off the existing landing or a bedroom, so the stairs stay where they are. If the floor levels do not match, a step or two may be needed inside the new room. Where a landing opening is not practical, a new stair from a converted garage is an option.

Can my garage take a room on top?

Sometimes, but it needs checking. Many garages are built on shallow footings with thin walls, designed only for a single storey. We dig a trial hole and inspect the walls, and the structural engineer decides whether to reuse them, strengthen them, underpin the footings or build new foundations inside the garage.

Nearby

We also cover places near Aston, including:

Other extensions in Aston

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

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