Extensions over a garage in Bonhill

Useful details for planning an extension over a garage in Bonhill.

Postcode districts: G82
County / area: Glasgow and Dunbartonshire, Scotland
Price region: Scotland
Guide price: £29,500–£43,000 (£1,640–£2,400 per m²)
Approval route: Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.
Nearest towns: Vale of Leven (0.8 miles), Alexandria (1.3 miles), Dumbarton (2.4 miles)
Distance to Glasgow: about 14.2 miles
First visit: Free, no obligation

About an extension over a garage

An extension over a garage suits you if you have an attached single garage beside the house and need an extra bedroom or a larger main bedroom with an en-suite. You get an inspection of the garage structure, a design that matches the house, the approvals your nation needs, structural design, a building warrant and the build, carried out by vetted teams working under S&K.

Around Bonhill we also work in Vale of Leven, Alexandria and Dumbarton, and across the rest of Glasgow and Dunbartonshire. Postcode district in and near Bonhill: G82.

What it costs in Bonhill

Our guide for Scotland is £1,640–£2,400 per m² including VAT. On a project with 3 m × 6 m of new first-floor space (18 m²), that puts an extension over a garage in Bonhill at roughly £29,500–£43,000. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	3 m × 6 m of new first-floor space (18 m²)
Essential	£1,510–£2,210 per m²	£27,000–£39,500
Standard	£1,640–£2,400 per m²	£29,500–£43,000
Premium	£1,970–£2,880 per m²	£35,500–£52,000

Planning and building standards in Bonhill

In Scotland, a room over a garage makes the extension more than one storey, so Class 1B applies, which needs at least 10 m to every boundary for permitted development. Attached garages are rarely that far from the boundary, so expect a householder application (£371, decided within two months) and a building warrant.

Approval in Scotland: Householder planning application: £371. Councils have two months to decide a local planning application.

Building standards: A building warrant from the council's building standards service before work starts, and a completion certificate at the end. Scotland uses its own Technical Handbooks.

Design points for Bonhill homes

Matching the house

A room over a garage usually sits beside the front of the house in full view, so roof form, ridge height, windows and brick matter. Setting the front wall and ridge back slightly from the main house usually helps it look as if it belongs.

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

Visit and first ideas
One of our team visits your house in Bonhill, checks the walls, roof and drains, and sketches out options with you.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Scotland before drawing in detail.
Detail and price
Construction drawings, engineer's calculations and building warrant approval, then a written fixed price for the build.
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 Bonhill

How much does an extension over a garage cost in Bonhill?

Our guide for Scotland, which covers Bonhill, is £1,640–£2,400 per m² including VAT. A typical project with 3 m × 6 m of new first-floor space (18 m²) comes to about £29,500–£43,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Who handles building standards for a project in Bonhill?

We handle it as part of the project. What's needed in Scotland: a building warrant from the council's building standards service before work starts, and a completion certificate at the end. Scotland uses its own Technical Handbooks. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

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

Bonhill is in Scotland. Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.

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.

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.

Nearby

Close to Bonhill? We work across the area, including:

Other extensions in Bonhill

All two-storey extension services in Bonhill · Extensions over a garage across Glasgow and Dunbartonshire

Tell us about your house in Bonhill and we'll call you back to arrange a free, no-obligation visit.