Extensions over a garage in Greenock
Thinking about an extension over a garage in Greenock? 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.
What we'd confirm first for a project in Greenock.
- Postcode districts
- PA15 and PA16
- County / area
- Renfrewshire and Inverclyde, 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
- Gourock (2.4 miles), Port Glasgow (2.9 miles), Helensburgh (4.2 miles)
- Distance to Paisley
- about 15.1 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 Greenock (PA15 and PA16) and the places around it, including Gourock (2.4 miles), Port Glasgow (2.9 miles) and Helensburgh.
What it costs in Greenock
Using our Scotland rates, an extension over a garage with 3 m × 6 m of new first-floor space (18 m²) comes to about £29,500–£43,000, including VAT. Bigger or more glazed designs cost more per m². Keep a contingency of around 10% for things nobody can see until the ground is opened up.
| 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 Greenock
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 Greenock homes
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.
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.
How we'd run your project
Visit and first ideas
One of our team visits your house in Greenock, checks the walls, roof and drains, and sketches out options with you.
Get it approved
Once you're happy with the design we submit it to the council for Greenock and deal with any questions from the planning officer.
Detail and price
Construction drawings, engineer's calculations and building warrant approval, then a written fixed price for the build.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.
Questions about extensions over a garage in Greenock
Who handles building standards for a project in Greenock?
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.
How long does an extension over a garage take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils have two months to decide a local planning application), 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 much does an extension over a garage cost in Greenock?
Our guide for Scotland, which covers Greenock, 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.
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 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
Close to Greenock? We work across the area, including:
Other extensions in Greenock
- Rear
- Side
- Wraparound
- Part two-storey
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Greenock · Extensions over a garage across Renfrewshire and Inverclyde
Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Greenock.