Garage Conversion Cost Calculator UK
The average garage conversion cost in the UK is £8,000 to £18,000 for a single garage in 2026, or roughly £800 to £1,200 per m² for a standard finish. A double garage conversion is typically £15,000 to £30,000. Adding an en-suite or kitchenette, or converting a detached garage, pushes the price up.
- Single garage£8,000 – £18,000
- Double garage£15,000 – £30,000
- Per m², standard finish£800 – £1,200
Prices checked November 2026 · UK figures include labour and materials unless stated
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Garage conversion prices UK (2026)
| Conversion | Typical cost |
|---|---|
| Single garage to study or playroom | £7,000 – £12,000 |
| Single garage to bedroom | £10,000 – £16,000 |
| Single garage to bedroom with en-suite | £14,000 – £22,000 |
| Double garage to open-plan room | £15,000 – £24,000 |
| Double garage to annexe (bed, bath, kitchenette) | £24,000 – £35,000 |
| Detached garage to living space | From about £18,000 |
London and the South East are usually the most expensive regions; Scotland and the North the cheapest.
Single garage conversion cost
A single garage conversion usually costs £8,000 to £18,000, depending on what you turn it into: about £7,000 to £12,000 for a study or playroom, £10,000 to £16,000 for a bedroom and £14,000 to £22,000 for a bedroom with an en-suite. The biggest costs are the new front wall and window, insulating and raising the floor, and any plumbing for a bathroom.
What a garage conversion includes
- Removing the garage door and building a new insulated wall with a window or French doors.
- Raising and insulating the floor (garage floors are usually lower than the house and uninsulated).
- Insulating walls and ceiling to meet building regulations, plus ventilation and a fire-safe escape route.
- Electrics, heating (often a new radiator or underfloor heating), plastering, decorating and flooring.
Planning permission and building regulations
Most garage conversions are permitted development, so planning permission is not needed if the work is internal and the outside does not change much. Check first if you live in a conservation area, a listed building, or a newer estate where permitted development rights have been removed. Building regulations approval is always needed for a habitable room: it covers insulation, fire safety, ventilation, damp-proofing and the strength of the new wall.
Is a garage conversion worth it?
Converting is usually much cheaper per square metre than building an extension, because the walls, roof and foundations already exist. An extra bedroom or office can add value, but check local demand for parking: in some streets buyers value a garage or off-road space more than an extra room.
How this garage conversion cost calculator works
We multiply the floor area by a 2026 price per m² for the finish you choose (£600 to £900 basic, £800 to £1,200 standard, £1,200 to £1,800 high spec), with about 15% off per m² for double garages because of economies of scale. Detached garages are about 20% more because services must be run to them. En-suite, kitchenette and fee allowances are added, then the total is adjusted for your region.
Frequently asked questions
How much does a garage conversion cost in the UK?
A single garage conversion typically costs £8,000 to £18,000 in 2026, and a double garage £15,000 to £30,000, depending on the finish and whether you add a bathroom or kitchen.
How much does a garage conversion cost per m²?
Most standard habitable conversions cost about £800 to £1,200 per m². Basic conversions can be around £600 per m², and high-spec ones £1,800 per m² or more.
Do I need planning permission to convert my garage?
Usually not, as most conversions are permitted development. You will need it if your property’s permitted development rights have been removed, it is listed, or you change the outside significantly. Building regulations approval is always required.
How long does a garage conversion take?
A straightforward single garage conversion usually takes 2 to 4 weeks on site. Adding a bathroom or converting a double or detached garage can take 6 to 8 weeks.
Does a garage conversion add value?
Often yes, especially where extra bedrooms are in demand. In areas where parking is scarce, losing the garage can put some buyers off, so check with a local estate agent.
Is converting a garage cheaper than an extension?
Yes, usually by a lot. Extensions cost around £1,800 to £3,000 per m², while garage conversions are typically £800 to £1,200 per m².
How much is a garage conversion?
Most single garage conversions cost £8,000 to £18,000 and double garage conversions £15,000 to £30,000 in 2026.
Where our prices come from
We compare published 2026 UK cost guides and trade price data, then use the middle of the range. Figures are for budgeting only and are not a quote. See how we price.