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 Hampshire?
In Hampshire, a garage conversion typically costs £20,000–£33,500 for a single integral garage, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for Hampshire are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A single integral garage | £20,000–£33,500 |
| Higher specification | £33,500–£42,000 |
What moves the price most:
- Foundations under the old door opening
- Single or double garage
- Heating and flooring
- 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 Hampshire?
Before anything is built in Hampshire, 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.
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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
From survey to sign-off, the job normally involves:
- Electrics, heating and plastering
- Wall and ceiling insulation
- Floor raised with insulation and damp-proof membrane
- Planning check for removed permitted development rights
- Foundation check under the garage door opening
- New wall and window to replace the garage door
How long does it take?
Build time is typically 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 Hampshire
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Towns we cover in Hampshire include Southampton, Portsmouth, Basingstoke, Gosport, Waterlooville and Farnborough.
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
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 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 Hampshire
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 long does a garage conversion take in Hampshire?
Typically 3 to 6 weeks on site. Design and approvals beforehand usually take 6 to 12 weeks.
How much does a garage conversion cost in Hampshire?
In Hampshire, a garage conversion typically costs £20,000–£33,500 for a single integral garage, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.
