How much does a garage conversion cost in the UK? (2026)

Verified UK garage conversion costs in 2026 for single and double garages, what's typically included, what's almost always missing from the headline figure, and how to spot a quote that's been priced as a refurbishment when it should be priced as a build.

A UK garage being converted into a habitable room with new insulation and partition walls.
Photo by Samuel Field on Unsplash

A garage conversion in the UK in 2026 costs between £10,500 for a basic single garage and £60,000+ for a premium double conversion with a bathroom and full integration into the main house. The mid-range, where most people sit, is £14,500 to £19,800 for a single, £16,200 to £27,000 for a double.

Quick answer

A single garage conversion in the UK in 2026 typically costs £10,500–£15,000 at the basic end (insulation, plasterboard, new floor, one window, electrics), £14,500–£19,800 mid-range (full re-skin, new heating, decent flooring, new doors), or £19,800–£32,000 premium (bathroom, kitchenette, opening into main house). Double garage: £16,200–£27,000 mid, up to £61,200 premium. Cost per m²: £1,000–£1,500. Typical timeline: 3–8 weeks.

How to read this guide#

Two kinds of figures appear below:

Where we could not verify a specific number against published cost guides, we have either left it out or described the item qualitatively.

Headline ranges (verified)#

Single garage conversion tiers, UK 2026:

TierRange
Basic£10,500 – £15,000
Mid-range£14,500 – £19,800
Premium£19,800 – £32,000

Double garage conversion tiers, UK 2026:

TierRange
Basic£16,200 – £19,800
Mid-range£19,800 – £27,000
Premium£27,000 – £61,200

Other verified figures:

Practical guidance (industry standard)#

What a garage conversion actually involves#

A garage conversion creates a habitable room out of what was a non-habitable space. The practical work breaks into seven categories:

  1. Floor: raising the floor level (garage floors typically slope toward the door for water runoff), adding insulation, screeding flat for finished flooring
  2. Walls: insulating from the inside (most common), battening, plasterboarding, skimming. Single-skin garage walls usually need a stud-and-insulation inner wall rather than just dot-and-dab boards
  3. Roof: checking the roof structure, insulating between rafters or above the ceiling line, plasterboarding the underside
  4. Garage door opening: removing the door, building up the opening in brick or block, installing a window (or french doors), rendering and finishing externally
  5. Electrics: new circuits, sockets to current spacing standards, lighting, possibly extending the consumer unit
  6. Heating and ventilation: extending central heating (radiators, pipework) or installing electric heating; trickle vents and extract fan if a wet room is included
  7. Internal finishing: flooring, skirting, architrave, doors, decoration

If your quote does not visibly account for all seven of these, ask why. The most common omission is heating (assumed to be a "later" cost) and floor insulation (priced as a screed only without insulation underneath).

What this price normally covers#

A complete-conversion quote in the UK should typically cover:

It often does not cover:

When comparing quotes, the easy mistake is comparing a £14,500 quote that includes a new central heating extension against a £12,000 quote that assumes you will heat the new room with a plug-in electric heater. Read the exclusions section before you compare totals.

Building Regulations: not optional#

Every UK garage conversion that creates a habitable room is notifiable under Building Regulations, regardless of whether planning permission is needed. The Regs cover:

A quote that does not mention Building Control or Building Regulations is incomplete. Either the contractor handles the application or you do — but someone has to.

Regional variation#

UK garage conversion prices vary by region. Labour is the bigger driver of regional difference; materials are nationally priced. Standard UK adjustments:

Treat these as rough adjustments rather than precise multipliers; actual variation depends on the contractor's location and how busy the local trade is.

Red flags in garage conversion quotes specifically#

Beyond the standard quote red flags (covered separately), some are specific to garage conversions:

Priced as a refurbishment, not a build. A quote that comes in at £6,000 to £8,000 for a single garage conversion is almost certainly treating the job as "tidy up the garage" rather than "build a new habitable room." It will not meet Building Regs and you will own the problem when you sell the house.

No mention of how the front wall infill is finished. Bricking up the old garage door opening is the most visible exterior change. A good quote specifies whether the new wall will be rendered to match, brick-faced to match, or finished some other way. "Build up opening with blockwork" alone is not enough.

No floor insulation specification. Garage floors are typically uninsulated concrete sloping toward the door. A quote that does not mention insulating the floor either plans to leave it cold (Building Regs failure) or has forgotten to price the insulation in.

No heating extension. A new habitable room needs heating. If the quote does not extend the central heating system or specify an alternative, the room will be cold and the contractor will quote the heating separately later, at a worse rate than they would have done inside the original quote.

"No structural work needed" without a survey. Removing the garage door is structural. The lintel above the new front window has to take the load the door frame was taking. A quote that says no structural work is needed without referring to a structural engineer's calculation is either inexperienced or hoping you will not ask.

Single-glazed window in the new opening. Saving £200 on the window costs you Building Regs sign-off and a colder room for the next 25 years. A real quote specifies double glazing for any new opening.

Comparing your quote#

The reliable way to know if a garage conversion quote is fair is to compare each line against the ranges above. The easier way (and the reason this site exists) is to paste your quote into the quote checker and get every line analysed against current UK rates, scope-checked against what is typically missing, and the contractor verified against Companies House.

The £14 cost is well below the level at which most homeowners would deliberate on a £15,000 garage conversion quote. The information you get back closes the gap between "this number looks roughly right" and "every line of this number checks out."

Got a quote you want checked?

Paste any UK contractor quote and Check the Quote compares every line item against current market rates, flags missing scope, and runs a Companies House check on the contractor. Free on your first project.

Frequently asked questions

How much does a garage conversion cost in the UK in 2026?
A single garage conversion costs £10,500 to £15,000 in the UK in 2026 (MyJobQuote, 2026). A double garage runs £16,200 to £27,000. A premium conversion with a bathroom, kitchenette or full open-plan integration into the main house can reach £19,800 to £61,200. The headline figure assumes the garage is structurally sound and connected to mains services.
What is the cost per square metre?
Garage conversions typically cost £1,000 to £1,500 per m² in the UK in 2026, based on standard quantity-surveying rates for habitable-room conversions. A typical single garage is 15–18m² internally; a double is 30–36m². The per-m² rate is lower than a full extension (£1,800–£3,000/m²) because the shell already exists, but higher than a refurbishment because the work creates a new habitable room subject to Building Regulations.
Do I need planning permission for a garage conversion?
Most garage conversions in England fall under Permitted Development if you stay within the existing footprint and the property isn't listed, in a conservation area, or under an Article 4 direction. You still need Building Regulations approval (not the same as planning) for insulation, ventilation, structural opening sizes, and fire safety. Some councils restrict garage conversions where dropping the off-street parking would push cars onto an already-congested street; check with your local planning authority before you commit.
What is not usually included in a garage conversion quote?
Common scope gaps in UK garage conversion quotes: a Building Regulations application fee (£300–£600 paid to the council), structural calculations if any walls are being removed (£500–£1,200), new electrical consumer-unit work if the garage was on a sub-circuit, central heating extension (radiators, pipework, boiler capacity check), upgrading the existing garage door opening to a wall with window (£1,500–£3,000 for blockwork, lintel, render and finish), internal joinery (skirting, architrave, doors) priced as a separate line, and decorating after handover.
How much deposit should I pay?
No more than 10–15% of the contract value. A higher deposit is a red flag, especially on a sub-£20,000 job where the contractor should have working capital to cover the opening week. The balance should be staged against work milestones: typically a payment at first-fix (insulation, plasterboard, wiring complete), another at second-fix (skim plastered, electrics live), and the final payment on completion with Building Control sign-off received. Pay the deposit by credit card if you can. Section 75 of the Consumer Credit Act covers card-paid deposits between £100 and £30,000 if the contractor fails to deliver.
How long does a garage conversion take?
A straightforward single garage conversion takes 3 to 5 weeks on site. A double garage or a conversion that includes plumbing for a bathroom or kitchenette runs 5 to 8 weeks. Add 4 to 8 weeks of lead time before work starts for Building Regulations application, structural calculations if needed, and any bespoke joinery on order. Conversions that involve opening through into the main house need careful sequencing to keep the existing room weather-tight during the cut-through.
Will a garage conversion add value to my house?
The general UK guideline is that a well-executed garage conversion adds 5–10% to property value, against a build cost that is usually well below 5% of property value, so the maths is often favourable. Two caveats: (1) in areas where off-street parking is highly valued (most cities, especially London), losing the garage as parking can offset some of the value gain; (2) if the conversion is visibly cheap (single skin walls left exposed, single-glazed window, low ceiling) the valuation uplift will be modest at best.
Can I convert an attached garage and an integral garage the same way?
No. An integral garage (under the main roof, sharing walls with habitable rooms) is the cheapest to convert because the shell is already insulated on shared walls, the floor often only needs raising and insulating, and the front wall infill is the main structural job. An attached garage (separate roof, abutting the house) costs 15–25% more because the walls are usually single-skin, the roof often needs lining and insulating from scratch, and the link into the house requires opening a load-bearing external wall.

Last updated: 20 May 2026