What is a garage conversion?
A garage conversion turns an integral or attached garage into habitable space, such as a study, playroom, bedroom or utility. The garage door is replaced with a wall and window, the floor is raised and insulated, and the walls and roof are brought up to building regulations.
How much does a garage conversion cost in Greater London?
In Greater London, a garage conversion typically costs £23,500–£39,000 for a single integral garage, including VAT at 20% (standard rate). That range is adjusted for London, where domestic building work typically costs around 30% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A single integral garage | £23,500–£39,000 |
| Higher specification | £39,000–£49,000 |
What moves the price most:
- Bathroom or kitchen
- Integral, attached or detached
- Heating and flooring
- Single or double garage
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a garage conversion in Greater London?
Before anything is built in Greater London, we confirm which approvals apply in England. In England converting an integral or attached garage usually does not need planning permission, unless a condition on the house removed permitted development rights (common on estates built in recent decades) or the house is listed. Building regulations approval is always needed.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical garage conversion we handle:
- Electrics, heating and plastering
- Foundation check under the garage door opening
- Floor raised with insulation and damp-proof membrane
- Building control completion
- New wall and window to replace the garage door
- Wall and ceiling insulation
How long does it take?
Expect 3 to 6 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Greater London
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Places we cover in Greater London include Acton, Balham, Barking, Barnes, Barnet and Battersea.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about garage conversions in Greater London
Do I need building regulations approval?
Yes. Converting a garage to a habitable room needs building control approval for insulation, ventilation, fire safety and the new wall.
How long does a garage conversion take in Greater London?
Typically 3 to 6 weeks on site. Design and approvals beforehand usually take 6 to 12 weeks.
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.
Will losing the garage affect parking?
Councils sometimes object if on-street parking is under pressure. We check local parking standards.
How much does a garage conversion cost in Greater London?
In Greater London, a garage conversion typically costs £23,500–£39,000 for a single integral garage, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.