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Garage conversion cost: single and double garages priced

2026 prices for single and double garage conversions by garage type and room, what a quote should include, the fees and VAT around the build, and the rules in each UK nation.

A single garage conversion costs £7,500 to £24,000 in 2026, and a double garage £12,000 to £38,400 or more. The bottom of each range is a basic room in an integral garage at North East prices. The top adds plumbing, a detached building or a high-spec finish. We price both sizes by garage type and by room, list what a quote should include, and set out the fees, VAT and rules around the build.

Garage conversion cost by garage size and type

Size and the way the garage joins the house set the price. A single garage gives 12 to 16 m² of floor and a double up to 26 m². An integral garage already shares walls, a roof and services with the house, so it is the cheapest to convert. A detached garage is the dearest, because it needs groundwork and water and power run out to it.

Garage conversion prices by garage type and size, 2026
GarageSingle garageDouble garage
Integral, from (North East prices)£7,500£12,000
Attached, from (North East prices)£9,000£14,000
Detached, from (North East prices)£10,000£16,000
Average basic build (North East prices)£10,500£16,000
Typical range, standard finish, UK£12,000 – £24,000£18,000 – £38,400+

The North East prices are for the building work alone, with flooring and decoration extra. The UK ranges are for a finished room at a standard specification.

Single garage conversion cost

A single garage makes one room: a bedroom, a home office or a playroom. A standard finish costs £12,000 to £24,000, and a standard 16 m² single averages about £13,500. By type, an integral single averages £13,800, an attached one £16,800 and a detached one £22,200.

Double garage conversion cost

A double garage gives up to 26 m², enough for two rooms or a small annexe. A standard finish averages around £28,200, and a detached double with full plumbing can pass £46,000.

Partial garage conversion cost

Converting the back of an integral garage and keeping the front as storage is the cheapest option, from £6,000 for an 8 m² room at North East prices. It suits a home office, and it keeps somewhere for bikes and bins.

Garage conversion cost by room

What the room is for moves the price more than its size. A bedroom or an office needs no water. An en suite or a kitchen needs new pipework, drainage, ventilation and waterproofing, and that is where a garage conversion gets expensive.

Garage conversion cost by room, 2026
RoomEstimated costMain cost drivers
Home office£9,600 – £14,400Network cabling, lighting, heating
Bedroom£12,000 – £18,000Insulation, fire-rated door, electrics
Living room or playroom£12,000 – £21,600Flooring, large windows, plastering
Bedroom with en suite£18,000 – £30,000Plumbing, drainage, tiling, extraction
Kitchen£18,000 – £36,000Plumbing, gas, extraction, units
Self-contained annexe£30,000 – £54,000+Kitchen, bathroom, separate entrance

Where the garage sits far from the house's drains and water supply, plumbing and drainage for a bathroom or kitchen adds £3,600 to £7,200 on its own. Turning the garage into a separate dwelling may also need planning permission, whatever the building work involves.

What a garage conversion quote includes

A basic garage conversion price should cover the building work that turns a garage into a room:

  • An infill wall on new foundations where the garage door was
  • A new uPVC window in that wall
  • Insulation and plasterboard on the walls and ceiling, finished with a plaster skim
  • Joinery: a door, skirting, architrave and a window sill
  • Electrics extended from the house for lights and sockets
  • Heating, either extended from the house system or as electric radiators

Finishes usually sit outside that price. These are supply-and-fit flooring prices for a 13 m² single and a 26 m² double.

Flooring supply and fit, by garage size
Floor finishPer m²Single, 13 m²Double, 26 m²
Carpet£20£260£520
Laminate£25£325£650
LVT click£38£500£1,000
Tiles£70£910£1,820

Tiles need a tiler on top, at around £35 per m². Decoration in emulsion and gloss runs from £500 for a single and around £900 for a double. A standard internal door costs under £30, while an FD30 fire door, one of the cost drivers in a bedroom conversion, costs from £100.

What pushes a garage conversion price up

  • The state of the garage. A structural survey costs £360 to £720. If the garage is not sound enough to convert, demolishing and rebuilding a single garage costs £18,000 to £36,000 in London, and most of those jobs land at £25,000 to £30,000.
  • Specification. A high-spec finish, with bespoke joinery, a wet room or underfloor heating, adds £6,000 to £12,000 or more.
  • Heating. A radiator off the house system or electric radiators sit in most basic prices. Underfloor heating pipework starts from £325, and fitting it costs at least as much again.

Garage conversion cost per square metre

Garage conversion cost per m², 2026
BuildCost per m²
Basic build, average double garage, North EastAbout £615
Basic build, average single garage, North EastAbout £810
Standard finish, UK£1,440 – £1,920
High spec: underfloor heating, bespoke joinery, wet room£2,400 – £3,000

At North East prices the average double works out about £200 per m² cheaper than the average single, because fixed parts of the job, such as the drawings, are spread over twice the floor. Use a per-metre rate to sense-check a quote, not to build one.

Garage conversion fees on top of the build

Two fees apply to every conversion. The rest depend on the house and the plans.

Garage conversion fees, 2026
FeeTypical costWhen you pay it
Building regulations drawings£240 – £1,200Every conversion
Building control fee£200 – £1,200Every conversion; a building notice for a simple job sits at the bottom
Structural survey£360 – £720Where the walls, roof or slab are in doubt
Planning application, professional fees£400 – £1,000Only where planning permission is needed
Householder planning application fee, England£548Only where planning permission is needed
Lawful development certificate, England£274Optional written confirmation that the work is lawful
Party wall agreementFrom £700 per neighbourWhere the work affects a shared wall
Restrictive covenant£200 – £720Where the title deeds restrict the conversion

There is no national building control fee. Councils set theirs from their own costs, based on the type of work, the inspections and the floor area, and a registered building control approver agrees a fee with you directly.

If the new foundations or walls sit on or near a boundary or a wall shared with a neighbour, you have to tell the neighbour before work starts in England and Wales, and a party wall agreement costs from £700 per neighbour. Scotland has different rules. Hold back another 10 to 15% of the build cost for what the builder finds once the garage is emptied and opened up.

VAT on a garage conversion

A garage conversion is work to an existing home, so it carries VAT at the standard 20%, the rate behind most house renovation costs. The builder charges it on labour and on the materials they supply, and materials you buy yourself are standard-rated too.

The reduced 5% rate applies to a conversion that changes the number of dwellings in a building. A garage turned into a room in the same house does not qualify. Check whether each quote includes VAT: on a £15,000 job it adds £3,000.

Garage conversion costs by region

Labour is the part of the price that moves with the postcode. Against North East rates, labour runs higher in every other region of England and in Wales.

Labour cost uplift against the North East
RegionLabour uplift
North West9%
Yorkshire and the Humber10%
East Midlands12%
West Midlands11%
East of England15%
South East12%
South West9%
London13% – 20%
Wales9%

On finished prices, London and the South East add 15 to 25% to the UK ranges. A standard single garage conversion in London therefore runs to about £13,800 to £30,000, where the same job costs £12,000 to £24,000 nationally.

Labour rates by trade

Trade rates on a garage conversion, 2026
TradeRate
Electrician£400 a day
Plasterer£300 a day
Plumber£325 – £375 a day
Joiner£240 – £360 a day
Kitchen fitter£250 – £350 a day
Window fitter£25 – £35 an hour

A plasterer at about £300 a day and an electrician at about £400 work on almost every conversion, because the walls and ceiling are boarded and skimmed and the house wiring is extended. The plumber, at £325 to £375 a day, comes in for a radiator, a bathroom or a kitchen.

Do you need planning permission for a garage conversion?

In England, planning permission for a garage conversion is not usually needed, providing the work is internal and does not enlarge the building. That is the test in the Planning Portal's garage conversion guidance, and it has exceptions:

  • Removed rights. Some homes have had their permitted development rights removed for garage conversions, particularly on new housing developments and in conservation areas. Ask the council before work starts.
  • A separate home. Converting a garage into a separate house may need planning permission whatever the work involves, and whoever lives in it.
  • Listed buildings. Work to a listed building may need listed building consent.
  • Flats, conditions and Article 4 directions. Permitted development applies to houses, not flats or maisonettes, and a planning condition or an Article 4 direction can limit it.

Where planning is needed, a householder application in England costs £548 from 1 April 2026. Where it is not, a lawful development certificate costs £274 and confirms in writing that the conversion is lawful.

Wales, Scotland and Northern Ireland

  • Wales: the Welsh Government's garage conversion guidance sets the same test as England. Rights may have been removed by a condition on the home's original planning permission or by an Article 4 direction.
  • Scotland: turning a garage into living space is a conversion under the Building (Scotland) Regulations 2004, and a conversion needs a building warrant. The warrant is granted only if the building meets the standards in regulation 12, as far as is reasonably practicable. Scottish permitted development rights also differ from England's.
  • Northern Ireland: planning and building control run as separate systems from England's, so check with the local council before any work starts.

Building regulations for a garage conversion

In England, converting a garage or part of one into habitable space normally needs approval under the building regulations, even when no planning permission is needed. Building control looks at the doors and windows, drainage, electrics, external and internal walls, the roof, the floor, the infill where the garage door was, walls below ground level and ventilation. In practice that means structure, fire safety and escape, insulation, ventilation and electrical safety.

Building regulations approval comes from the council's building control team or a registered building control approver. A full plans application gets a decision within 5 weeks, or 2 months if you agree. A building notice suits simpler jobs: work can start 2 days after it goes in, without formal approval, and some councils charge around £200 for a simple conversion.

A full plans job that complies gets a completion certificate, usually within 8 weeks of the work finishing. A buyer's solicitor asks for it when you sell.

How long a garage conversion takes

A standard garage conversion takes 2 to 4 weeks on site, and a complex one 6 to 8 weeks. A straightforward single runs in this order:

A standard garage conversion, week by week
WeekWork on site
Week 1Structural work: the infill wall on its foundation and the window opening
Week 2First fix: cables and pipes run before the walls are boarded
Week 3Second fix: sockets, switches, lights and radiators connected after plastering
Week 4Finishing: flooring, doors, decoration and the final building control inspection

Drawings and approval come before week 1. Give builders 4 to 8 weeks' notice when you ask for quotes, and the prices tend to come in keener.

Garage conversion or extension: which costs less?

A garage already has walls, a roof and a floor slab, so converting it costs a fraction of building new space and takes weeks rather than months.

Garage conversion against a loft or an extension, 2026
ProjectTypical costTime on site
Single garage conversion£7,500 – £24,0002 – 4 weeks
Double garage conversion£12,000 – £38,400+2 – 8 weeks
Loft conversion, including VAT£30,000 – £96,000+4 – 12 weeks
Single-storey rear extension, 20 – 30 m²£60,000 – £90,0008 – 16 weeks

Measured by the metre, a single-storey extension starts at about £2,500 per m², against £1,440 to £1,920 for a garage conversion at a standard finish. A loft conversion keeps the garage and adds a room upstairs, but costs at least £30,000.

An extension or a loft is the better buy when the garage is your only off-road parking or storage, or when you need more space than the garage holds.

Does a garage conversion add value?

A well-finished garage conversion can add 10 to 15% to a home's value. On a £300,000 house that is £30,000 to £45,000, more than a standard single conversion costs. The uplift is not guaranteed: it rests on the room you create and on whether buyers on your street want the space more than the garage.

Common questions

How much does it cost to convert a garage into a room in the UK?

Converting a single garage into a room costs £7,500 to £24,000 in 2026, and a double garage £12,000 to £38,400 or more. A basic build in an integral garage at North East prices sits at the bottom. Plumbing, a detached garage, a high-spec finish or a London postcode push the price towards the top.

How much does a double garage conversion cost?

A double garage conversion costs £18,000 to £38,400 or more at a standard finish in 2026, and averages around £28,200. A basic build at North East prices starts at £12,000 and averages £16,000. A detached double with full plumbing can pass £46,000.

How much does it cost to convert a garage into a bedroom?

Converting a garage into a bedroom costs £12,000 to £18,000, or £18,000 to £30,000 with an en suite. The bedroom price covers insulation, electrics and a fire-rated door. The en suite adds plumbing, drainage, tiling and extraction, and the plumbing and drainage alone can cost £3,600 to £7,200.

How much is a garage conversion per square metre?

A garage conversion costs £1,440 to £1,920 per m² at a standard finish and £2,400 to £3,000 per m² at a high spec. A basic build at North East prices averages about £810 per m² for a single garage and £615 for a double, because fixed costs are spread over more floor.

Do I need permission to convert my garage into a room?

In England and Wales a garage conversion does not usually need planning permission if the work is internal and does not enlarge the building. It can need permission where permitted development rights have been removed, particularly on new housing developments, and a separate dwelling may need permission whatever the work. Building regulations approval is normally needed either way.

Do you need a building warrant to convert a garage in Scotland?

Yes, a garage conversion in Scotland needs a building warrant, because turning a garage into living space counts as a conversion under the Building (Scotland) Regulations 2004. The warrant is granted only if the building meets the standards in regulation 12, as far as is reasonably practicable. Scotland's permitted development rules also differ from England's.

Is it cheaper to convert a garage or build an extension?

Converting a garage is far cheaper than building an extension. A single garage conversion costs £7,500 to £24,000, while a 20 to 30 m² single-storey rear extension costs £60,000 to £90,000. The garage already has walls, a roof and a slab, and the work takes 2 to 4 weeks on site against 8 to 16 weeks for an extension.

Are garage conversions worth it?

A garage conversion is worth it when you need the room more than the parking or storage. It can add 10 to 15% to a home's value, which on a £300,000 house is £30,000 to £45,000, more than a standard single conversion costs. Where parking is scarce on your street, ask a local estate agent first.

How long does a garage conversion take?

A standard garage conversion takes 2 to 4 weeks on site, and a complex one 6 to 8 weeks. Drawings and building regulations approval come first, and a full plans decision can take up to 5 weeks, or 2 months with your consent. Building control makes a final inspection once the work is finished.

What is the cheapest way to convert a garage?

The cheapest conversion is a partial one in an integral garage, from £6,000 for an 8 m² room at North East prices. A home office with no plumbing is the cheapest full room, at £9,600 to £14,400. Doing the decorating and other finishing yourself saves £1,200 to £2,400.

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