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 Hertfordshire?
In Hertfordshire, a garage conversion typically costs £19,000–£32,000 for a single integral garage, including VAT at 20% (standard rate). Prices across the East of England are typically 6% above the UK average for this kind of work, which is reflected in the range for Hertfordshire. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A single integral garage | £19,000–£32,000 |
| Higher specification | £32,000–£40,000 |
What moves the price most:
- Foundations under the old door opening
- Bathroom or kitchen
- Single or double garage
- Integral, attached or detached
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 Hertfordshire?
Approvals for a garage conversion in Hertfordshire follow the rules for 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
From survey to sign-off, the job normally involves:
- Electrics, heating and plastering
- Floor raised with insulation and damp-proof membrane
- New wall and window to replace the garage door
- Planning check for removed permitted development rights
- Drawings and building control application
- Foundation check under the garage door opening
How long does it take?
The build itself usually takes 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 Hertfordshire
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
Towns we cover in Hertfordshire include Watford, Hemel Hempstead, Stevenage, St Albans, Welwyn Garden City and Cheshunt.
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
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about garage conversions in Hertfordshire
Can a detached garage be converted?
Yes, but using it as separate living accommodation may need planning permission.
How long does a garage conversion take in Hertfordshire?
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 Hertfordshire?
In Hertfordshire, a garage conversion typically costs £19,000–£32,000 for a single integral garage, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Do I need planning permission for a garage conversion?
Usually not if the work is internal and the house keeps its permitted development rights. Many newer houses have planning conditions that remove those rights, in which case an application is needed.
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.