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 Coulsdon?
In Coulsdon, a garage conversion typically costs £23,500–£39,000 for a single integral garage, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for London, where labour and materials are typically about 30% above 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 |
Your quote will depend mainly on:
- Heating and flooring
- Bathroom or kitchen
- Whether planning permission is needed
- Integral, attached or detached
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 Coulsdon?
Here is how the rules work for a garage conversion 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most garage conversions:
- Foundation check under the garage door opening
- Drawings and building control application
- Floor raised with insulation and damp-proof membrane
- Electrics, heating and plastering
- Planning check for removed permitted development rights
- Wall and ceiling insulation
How long does it take?
Build time is typically 3 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Coulsdon
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Our Coulsdon coverage includes postcode districts CR5, and we also work in nearby places such as Purley, Wallington and Banstead.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about garage conversions in Coulsdon
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.
Who approves a garage conversion in Coulsdon?
Planning matters in Coulsdon go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Will losing the garage affect parking?
Councils sometimes object if on-street parking is under pressure. We check local parking standards.
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.
How much does a garage conversion cost in Coulsdon?
In Coulsdon, 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.
