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 West Sussex?
In West Sussex, a garage conversion typically costs £20,000–£33,500 for a single integral garage, including VAT at 20% (standard rate). That range is adjusted for the South East, where domestic building work typically costs around 12% above the national average. 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 |
The biggest cost drivers are:
- Heating and flooring
- Single or double garage
- Whether planning permission is needed
- Bathroom or kitchen
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a garage conversion in West Sussex?
The approval route for West Sussex 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.
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
On a typical garage conversion we handle:
- Drawings and building control application
- Wall and ceiling insulation
- Building control completion
- Foundation check under the garage door opening
- Electrics, heating and plastering
- New wall and window to replace the garage door
How long does it take?
Expect 3 to 6 weeks on site. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in West Sussex
The South East has a broad mix of housing, from Victorian terraces in the towns to post-war semis and newer estates, so extension types vary street by street.
Towns we cover in West Sussex include Crawley, Worthing, Bognor Regis, Littlehampton, Horsham and Haywards Heath.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and 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 West Sussex
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.
Will losing the garage affect parking?
Councils sometimes object if on-street parking is under pressure. We check local parking standards.
How long does it take?
Typically 3 to 6 weeks on site.
How much does a garage conversion cost in West Sussex?
In West Sussex, 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.
Who approves a garage conversion in West Sussex?
Planning matters in West Sussex go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.