Extensions over a garage in Timperley
Our extensions over a garage service in Timperley covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
The basics for Timperley at a glance.
- Postcode districts
- M23
- County / area
- Greater Manchester, England
- Price region
- North West England
- Guide price
- £30,000–£43,500 (£1,660–£2,420 per m²)
- Approval route
- Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
- Nearest towns
- Altrincham (1.1 miles), Hale (Greater Manchester) (1.5 miles), Sale (1.8 miles)
- Distance to Manchester
- about 6.8 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.
Timperley sits about 6.8 miles from Manchester. Closer to home, Altrincham is 1.1 miles away and Hale (Greater Manchester) 1.5 miles.
What it costs in Timperley
Guide prices for extensions over a garage in North West England are around £1,660–£2,420 per m² of new floor space, including VAT. For a typical project with 3 m × 6 m of new first-floor space (18 m²), that's roughly £30,000–£43,500. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| Spec | Per m² | 3 m × 6 m of new first-floor space (18 m²) |
|---|---|---|
| Essential | £1,530–£2,230 per m² | £27,500–£40,000 |
| Standard | £1,660–£2,420 per m² | £30,000–£43,500 |
| Premium | £1,990–£2,910 per m² | £36,000–£52,500 |
Planning and building regulations in Timperley
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 Timperley 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 Timperley, checks the walls, roof and drains, and sketches out options with you.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
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 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 Timperley
Who handles building regulations for a project in Timperley?
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.
Which postcodes do you cover around Timperley?
We cover Timperley (M23) and nearby places including Altrincham, Hale (Greater Manchester) and Sale, plus the rest of Greater Manchester. The first site visit is free.
Do I need planning permission for an extension over a garage in Timperley?
Timperley 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 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 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
Nearby towns we cover for extensions over a garage:
Other extensions in Timperley
- Rear
- Side
- Wraparound
- Part two-storey
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Timperley · Extensions over a garage across Greater Manchester
Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Timperley.