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.
Whatever prompted you to look into a garage conversion, whether wear and tear, a growing family or plans to move, we can survey your Mitcham home and give you a price in writing. Homes in London typically come in at £15,500–£36,500, VAT included, for this kind of work. We also cover Morden, Wimbledon and Streatham, and the same steps apply wherever you are in London.
- Guide price
- £15,500–£36,500 inc VAT
- Time on site
- 2–6 weeks on site
- Postcodes
- CR4, SM4, SM5, SW16 and SW17
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
Garage conversions prices in Mitcham
In Mitcham, guide figures for a garage conversion sit at £15,500–£36,500, VAT included. We set them using rates for London, currently about 30% above the national guide. The table shows what pushes a project towards either end of the range; your own price is set after a free survey.
| Type of job | What it usually involves | Guide in Mitcham |
|---|---|---|
| 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 |
Your price depends mostly on:
- Garage type: integral, attached or detached
- Condition of the floor, walls, roof and foundations
- Whether a shower room or kitchenette is included
- Window and door choices and the level of finishes
What do you get?
- 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
- Electrics, heating and ventilation by qualified trades, with certificates
- Plastering, skirting and decoration-ready finish
What are homes like around Mitcham?
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.
London Clay shrinks and swells with the seasons, and street trees close to houses can contribute to movement, which affects foundation design.
If your house in Mitcham fits one of these patterns, it helps us anticipate what a garage conversion will involve, though we always confirm the details on site.
Permissions for a garage conversion in Mitcham
England, Wales, Scotland and Northern Ireland each handle planning a little differently. Mitcham comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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.
How does the job run?
Free site survey
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a garage conversion so the price reflects your home.
Written quote
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Dates and permissions
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a garage conversion are in place before the first day on site.
The work itself
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
How we work
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 for a garage conversion?
Whether a garage conversion needs planning permission depends on the works, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, converting an integral or attached garage is often permitted development where changes are mostly internal, unless a planning condition has removed those rights, which is common on newer estates. We check what applies before quoting.
How much does a garage conversion cost?
A typical single garage conversion costs £15,500–£36,500, depending on whether the garage is integral, attached or detached and what the room is for. Integral garages usually cost least because the walls and roof are already sound. Adding a shower room, upgrading a flat roof or levelling a sloping floor adds cost. As a guide, allow roughly £550–£1,100 per square metre plus fixed costs. We confirm a fixed price after the survey.
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.
Can you combine a garage conversion with other work?
Yes. Because we manage several trades under one contract, we can plan a garage conversion alongside other work on your Mitcham home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
Near Mitcham
Live in Mitcham? Our coverage takes in the CR4, SM4, SM5 and SW16 postcode areas and reaches out to Morden, Wimbledon and Streatham, so homes on the outskirts and in the next town along are included.