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 Hounslow?
In Hounslow, 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 |
The biggest cost drivers are:
- Foundations under the old door opening
- Bathroom or kitchen
- Integral, attached or detached
- Whether planning permission is needed
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a garage conversion in Hounslow?
The approval route for Hounslow is set by planning law 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
What we take care of:
- Planning check for removed permitted development rights
- New wall and window to replace the garage door
- Electrics, heating and plastering
- Foundation check under the garage door opening
- Drawings and building control application
- Floor raised with insulation and damp-proof membrane
How long does it take?
The build itself usually takes 3 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Hounslow
Victorian and Edwardian terraces dominate many London streets, which is why side return, wraparound and mansard projects are so common here.
Projects in Hounslow (TW3, TW4 and TW6) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about garage conversions in Hounslow
How long does it take?
Typically 3 to 6 weeks on site.
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.
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 Hounslow?
In Hounslow, 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.
Who approves a garage conversion in Hounslow?
Planning matters in Hounslow go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.