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 Cardiff?
In Cardiff, a garage conversion typically costs £16,500–£27,500 for a single integral garage, including VAT at 20% (standard rate). Building costs in Wales run about 8% below the UK average, and the figures for Cardiff are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A single integral garage | £16,500–£27,500 |
| Higher specification | £27,500–£34,500 |
The main things that change the cost:
- Heating and flooring
- Bathroom or kitchen
- Whether planning permission is needed
- 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 Cardiff?
The approval route for Cardiff is set by planning law in Wales. In Wales converting a garage usually does not need planning permission unless rights have been removed by a planning condition; building regulations approval is always needed.
The Party Wall etc. Act 1996 applies in Wales, so notices must be served before work on a shared wall, on the boundary, or excavation close to a neighbour’s foundations.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
The work we manage on a garage conversion:
- Drawings and building control application
- New wall and window to replace the garage door
- Planning check for removed permitted development rights
- Floor raised with insulation and damp-proof membrane
- Foundation check under the garage door opening
- 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 Cardiff
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
Our Cardiff coverage includes postcode districts CF10, CF11, CF14 and CF15, and we also work in nearby places such as Penarth, Caerphilly and Barry.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about garage conversions in Cardiff
Will losing the garage affect parking?
Councils sometimes object if on-street parking is under pressure. We check local parking standards.
Can a detached garage be converted?
Yes, but using it as separate living accommodation may need planning permission.
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.
Do I need planning permission for a garage conversion in Cardiff?
In Wales converting a garage usually does not need planning permission unless rights have been removed by a planning condition; building regulations approval is always needed.
Who approves a garage conversion in Cardiff?
Planning matters in Cardiff go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How much does a garage conversion cost in Cardiff?
In Cardiff, a garage conversion typically costs £16,500–£27,500 for a single integral garage, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.