Extensions over a garage in Yarm
Thinking about an extension over a garage in Yarm? 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 Yarm.
- Postcode districts
- TS15 and TS16
- County / area
- County Durham, England
- Price region
- North East England
- Guide price
- £28,500–£41,500 (£1,580–£2,300 per m²)
- Approval route
- Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
- Nearest towns
- Thornaby-on-Tees (3.1 miles), Stockton-on-Tees (4.7 miles), Billingham (6.5 miles)
- Distance to Darlington
- about 7.9 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, building regulations approval and the build, carried out by vetted teams working under S&K.
We cover Yarm (TS15 and TS16) and the places around it, including Thornaby-on-Tees (3.1 miles), Stockton-on-Tees (4.7 miles) and Billingham.
What it costs in Yarm
Most of the cost of an extension over a garage is set by its size and specification. For Yarm and the rest of North East England, our guide is £1,580–£2,300 per m² including VAT, so about £28,500–£41,500 for 3 m × 6 m of new first-floor space (18 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 | £1,450–£2,110 per m² | £26,000–£38,000 |
| Standard | £1,580–£2,300 per m² | £28,500–£41,500 |
| Premium | £1,890–£2,750 per m² | £34,000–£49,500 |
Planning and building regulations in Yarm
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 Yarm homes
Fire separation
If the garage stays a garage, the floor between it and the room above, and any door into the house, must give fire separation under building regulations. That usually means fire-resisting plasterboard ceilings, sealed gaps and a fire door, which we design in from the start.
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
Start at your house
We come to your home in Yarm, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
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.
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 Yarm
Which postcodes do you cover around Yarm?
We cover Yarm (TS15 and TS16) and nearby places including Thornaby-on-Tees, Stockton-on-Tees and Billingham, plus the rest of County Durham. The first site visit is free.
How much does an extension over a garage cost in Yarm?
Our guide for North East England, which covers Yarm, is £1,580–£2,300 per m² including VAT. A typical project with 3 m × 6 m of new first-floor space (18 m²) comes to about £28,500–£41,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Do I need planning permission for an extension over a garage in Yarm?
Yarm 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.
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.
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
We also cover places near Yarm, including:
Other extensions in Yarm
- Rear
- Side
- Wraparound
- Part two-storey
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Yarm · Extensions over a garage across County Durham
Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Yarm.