How Much Does a Garage Conversion Cost in the UK?
The figures below are third-party estimates, not our prices. They are useful for early budgeting, but only a quote based on your property can give you a real figure.
The Federation of Master Builders gives a typical range of £7,000 to £32,000, with a standard 16 square metre garage averaging around £13,500. MyJobQuote's 2026 cost guide gives a wider range of £8,000 to £45,000, as it includes larger and higher-specification projects.
Is it cheaper in the North East?
It may be. MyJobQuote suggests that prices in Northern England can be 10 to 20% below the national average, while London and the South East are higher. Treat this as a rough guide, because your garage's condition will usually matter more than your postcode.
Cost by Type of Garage
Integral garages are usually the cheapest to convert, because they are already part of the house. Detached garages cost the most, as services have to be brought across to them.
| Garage type | Typical cost | Cost per m² |
|---|---|---|
| Integral | £10,000 to £14,000 | £450 to £750 |
| Attached | £10,000 to £20,000 | £805 to £1,100 |
| Detached | £20,000 to £31,000 | £1,100 to £1,700 |
| Detached double | £20,500 to £45,000 | Not published |
Cost by Type of Room
The room itself has a big effect on the price. Anything that needs water and drainage costs more than a dry room, such as an office.
| New room | Basic | Mid-range | Premium |
|---|---|---|---|
| Home office or hobby room | £8,000 to £12,000 | £12,000 to £18,000 | £18,000 to £25,000 |
| Bedroom without en-suite | £10,000 to £15,000 | £15,000 to £22,000 | £22,000 to £30,000 |
| Bedroom with en-suite | £15,000 to £22,000 | £22,000 to £32,000 | £32,000 to £45,000 |
The same guide lists a partial conversion at £5,500 to £8,500. A garage kitchen or annexe usually sits towards the higher end, as it needs more plumbing, electrics and ventilation.
Where Does the Money Go?
These published allowances show how a total builds up. Not all of them will apply to your project.
| Item | Published allowance |
|---|---|
| Front wall and structural work, integral garage | £3,000 to £6,000 |
| Insulation and damp-proofing | £1,500 to £5,000 |
| Structural engineer, where load-bearing walls are affected | £500 to £1,200 |
| Architectural drawings | £500 to £2,500 |
| Building control fees | £300 to £1,200 |
| Plumbing | £2,500 to £5,000 |
| Added bathroom | £5,500 to £9,000 |
| Utility connections, detached garage | £1,000 to £4,000 |
| Contingency | 10 to 15% of the budget |
What Pushes a Garage Conversion Price Up or Down?
Two garages of the same size can produce very different prices. Most of the gap comes from what is already there and what the new room needs.
The condition of the garage
Wall and roof condition, floor levels, the state of the concrete slab and any damp all matter. An old flat roof or a cracked floor means more work before the finishes can start.
How it connects to the house
A new doorway through a load-bearing wall needs support. Long pipe or cable runs also add to the cost, particularly in a detached garage.
Structural changes and windows
Knocking through to the house usually means an engineer's design and a steel beam. Larger windows or bifold doors cost more than a simple window in the old door opening.
Your choice of finishes
Flooring, underfloor heating, fitted storage, kitchen units and bathroom fittings can move the total by thousands of pounds. Agree what is included before you compare prices.
Is a Conversion Cheaper Than an Extension?
Usually, yes. The foundations, walls and roof already exist, so there is less to build from scratch. An extension may still suit you better if you need more space than the garage can give, or if you want to keep part of the garage. A conversion also keeps your garden intact.
Do You Pay VAT on a Garage Conversion?
Most building work on an existing home is charged at the standard rate of VAT, so check whether a quote includes it. A price that looks lower may simply exclude VAT. There are some exceptions, including work to create a new separate dwelling, so ask an accountant or HMRC if that applies to you.
How Can You Keep the Cost Down?
The simplest savings come from decisions made early:
- Keep plumbing close to existing pipes and drains
- Use the existing doorway from the house where you can
- Choose a standard window size for the old door opening
- Do some of the decorating yourself, if you are confident
- Fix the layout before work starts, as late changes cost more
Don't cut corners on insulation or damp-proofing. These are hard to put right later, and you will feel the difference every winter.
How Should You Pay for the Work?
Agree a payment schedule before anything starts, linked to clear stages such as the front wall, the first fix and completion. Be wary of paying a large sum up front, and keep a final payment back until the snagging list is finished.
What Should a Written Quote Include?
A lower price may simply assume less insulation, fewer electrical items or no approvals, so compare what each quote covers. It should list the building work, electrics, plumbing, decorating and waste removal, along with clear exclusions.
Check who is responsible for drawings, structural calculations and building control, and how any extra work would be priced. A reliable figure needs to be based on your property and an agreed scope, which is why we ask about your garage first.
Why Ask Us to Price Your Conversion?
We price from your actual garage, not a standard rate per square metre. Your quote will show what is included and what isn't, so you can compare it fairly against others. We cover homes across Newcastle upon Tyne, and we will tell you early if a cheaper layout would do the same job.