Extensions over a garage in Denton Holme
Our extensions over a garage service in Denton Holme covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Useful details for planning an extension over a garage in Denton Holme.
- Postcode districts
- CA1, CA2, CA4 and CA5
- County / area
- Cumbria, 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
- Carlisle (0.7 miles), Longtown (8.7 miles), Brampton (9.4 miles)
- Distance to Carlisle
- about 0.7 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 Denton Holme (CA1, CA2, CA4 and CA5) and the places around it, including Carlisle (0.7 miles), Longtown (8.7 miles) and Brampton.
What it costs in Denton Holme
Using our North West England rates, an extension over a garage with 3 m × 6 m of new first-floor space (18 m²) comes to about £30,000–£43,500, including VAT. Bigger or more glazed designs cost more per m². 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 Denton Holme
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 Denton Holme 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.
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.
How we'd run your project
Understand the brief
At your home in Denton Holme we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
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 Denton Holme
Which postcodes do you cover around Denton Holme?
We cover Denton Holme (CA1, CA2, CA4 and CA5) and nearby places including Carlisle, Longtown and Brampton, plus the rest of Cumbria. The first site visit is free.
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.
Who handles building regulations for a project in Denton Holme?
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.
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.
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.
Nearby
The same service in neighbouring towns:
Other extensions in Denton Holme
- Rear
- Side
- Wraparound
- Part two-storey
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Denton Holme · Extensions over a garage across Cumbria
Tell us about your house in Denton Holme and we'll call you back to arrange a free, no-obligation visit.