A garage conversion turns an integral or attached garage into a warm, habitable room by insulating the floor, walls and ceiling, replacing the garage door with a wall and window, and adding heating, lighting and finishes.
Across London, people look into a garage conversion to replace something worn out, to make the house work better for them, or to get it ready for a sale. We cover Brent, Islington, Westminster and Bexley and the smaller towns around them, working to the rules that apply in England. Expect a guide of £15,500–£36,500, VAT included, in London, and every quote follows a free visit.
- Guide price
- £15,500–£36,500 inc VAT
- Time on site
- 2–6 weeks on site
- Planning rules
- England
- Price level
- About 30% above the national guide
- Towns listed
- 90
- Survey
- Free, with a written quote
How much does a garage conversion cost in London?
Prices for a garage conversion vary from house to house, but in London most projects fall within £15,500–£36,500 including VAT. That reflects costs in London, about 30% above the national guide. Treat the table as a budgeting aid; the written figure follows a survey we carry out for free.
| Type of job | What it usually involves | Guide in London |
|---|---|---|
| Integral single garage | A garage within the house footprint, with sound walls and a roof already in place. | £13,000–£23,500 |
| Attached single garage | A garage beside the house that may need roof, wall or floor upgrades. | £18,000–£32,500 |
| Double or detached garage | A larger or separate building, often with a shower room or kitchenette. | £28,500–£58,000 |
What moves the price up or down:
- Garage type: integral, attached or detached
- Condition of the floor, walls, roof and foundations
- Heating method and ventilation for the new room
- Window and door choices and the level of finishes
What’s included?
- Infilling the garage door opening with insulated wall and new window
- Foundation checks under the door opening and footings where needed
- Damp-proof membrane, insulated floor and screed or raised timber floor
- Insulated walls and ceiling built to building regulations
- New internal door or opening into the house
- Electrics, heating and ventilation by qualified trades, with certificates
Housing across London
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
Terraces suit side-return extensions and rear dormer loft conversions; interwar semis commonly take hip-to-gable lofts. Shared party walls, restricted parking and conservation rules often shape the plans and the programme.
London Clay shrinks and swells with the seasons, and street trees close to houses can contribute to movement, which affects foundation design.
Do you need permission in London?
Each UK nation sets its own consent rules, and London is in England. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
In England, converting an attached or integral garage into a room usually needs no planning permission, unless a planning condition on your estate has removed permitted development rights (common on newer houses). Changing the garage door to a wall and window is generally fine.
Building Regulations approval is needed: foundations for the infill wall, a damp-proof course, insulation, ventilation and fire safety.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
The four stages
A visit to your home
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Quote in writing
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Getting ready
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your London property.
Build and hand over
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Frequently asked questions
How long will a garage conversion take?
On a typical home, allow 2–6 weeks on site. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
Do I need planning permission in London?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. London is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
Can I keep some storage space?
Many people keep part of the garage for storage by building a dividing wall, leaving a smaller store at the front behind the existing door and converting the area behind into a room or utility. This keeps the look of the house unchanged and gives you somewhere for bikes and tools. The converted part still needs the same insulation, ventilation and fire separation.
Does the floor need raising?
Garage floors are usually lower than the house floor and slope towards the door for drainage. Most conversions raise the floor with a damp-proof membrane, insulation and either a screed or a timber floor, so it lines up with the house and removes the step. The final level depends on ceiling height and the door into the house. We measure both during the survey.
How long does a garage conversion take?
A straightforward integral garage conversion usually takes two to four weeks on site. Attached garages that need roof or wall upgrades, and conversions with a shower room, typically take four to six weeks. Detached garages turned into annexes can take longer. Before work starts, allow time for drawings and building control approval. We give you a clear programme with your written quote.
Towns in London
Homes in all of the following London towns can get a written quote for a garage conversion. Open a town page to see prices and the postcodes we cover.
- Acton
- Archway
- Barking
- Barnes
- Barnet
- Battersea
- Beckenham
- Becontree
- Bexley
- Blackheath
- Blackwall
- Bow
- Brent
- Brixton
- Camden Town
- Canary Wharf
- Canning Town
- Carshalton
- Catford
- Chalk Farm
- Chelsea
- Chessington
- Chingford
- Chiswick
- Coulsdon
- Cricklewood
- Croydon
- Dagenham
- East Barnet
- Edmonton
- Eltham
- Enfield Town
- Feltham
- Finchley
- Fulham
- Golders Green
- Greenford
- Greenwich
- Hadley Wood
- Hampton
- Hanworth
- Harrow
- Hayes
- Heston
- Highbury
- Holloway
- Hook
- Hornchurch
- Hounslow
- Ilford
- Isleworth
- Islington
- Kilburn
- Leytonstone
- Mitcham
- Morden
- Muswell Hill
- New Malden
- Northolt
- Notting Hill
- Peckham
- Pimlico
- Pinner
- Purley
- Putney
- Richmond
- Romford
- Ruislip
- Shepherds Bush
- Soho
- South Croydon
- Southall
- Stamford Hill
- Stratford
- Streatham
- Surbiton
- Sutton
- Thamesmead
- Tottenham
- Uxbridge
- Wallington
- Walthamstow
- Wealdstone
- Welling
- Wembley
- Westminster
- Willesden
- Wimbledon
- Wood Green
- Woodford Green