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 Gwynedd?
In Gwynedd, a garage conversion typically costs £16,500–£27,500 for a single integral garage, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for Wales, where labour and materials are typically about 8% below average. 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 biggest cost drivers are:
- Single or double garage
- Whether planning permission is needed
- Heating and flooring
- Bathroom or kitchen
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a garage conversion in Gwynedd?
The approval route for Gwynedd 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.
Building regulations in Wales are set by the Welsh Government. Approval comes from the council’s building control service or a registered building control approver, with inspections during the work and a completion certificate at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
From survey to sign-off, the job normally involves:
- Wall and ceiling insulation
- Building control completion
- Electrics, heating and plastering
- New wall and window to replace the garage door
- Drawings and building control application
- Floor raised with insulation and damp-proof membrane
How long does it take?
Expect 3 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Gwynedd
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
Towns we cover in Gwynedd include Bangor, Llandudno, Holyhead and Caernarfon.
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
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about garage conversions in Gwynedd
Who approves a garage conversion in Gwynedd?
Planning matters in Gwynedd go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
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.
Do I need planning permission for a garage conversion in Gwynedd?
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.
How much does a garage conversion cost in Gwynedd?
In Gwynedd, 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.
How long does it take?
Typically 3 to 6 weeks on site.
