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 Stevenage?
In Stevenage, 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 Stevenage. 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 |
The biggest cost drivers are:
- Integral, attached or detached
- Heating and flooring
- Single or double garage
- Foundations under the old door opening
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 Stevenage?
Approvals for a garage conversion in Stevenage 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
On a typical garage conversion we handle:
- Planning check for removed permitted development rights
- Drawings and building control application
- Electrics, heating and plastering
- New wall and window to replace the garage door
- Foundation check under the garage door opening
- Floor raised with insulation and damp-proof membrane
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 Stevenage
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
Our Stevenage coverage includes postcode districts SG1, and we also work in nearby places such as Hitchin, Letchworth Garden City and Welwyn Garden City.
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 in place
We handle planning, building control and neighbour notices before work starts.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about garage conversions in Stevenage
Can a detached garage be converted?
Yes, but using it as separate living accommodation may need planning permission.
Do you build garage conversions in Stevenage?
Yes. We build garage conversions across Stevenage, including postcodes SG1. Every project starts with a free home visit.
How much does a garage conversion cost in Stevenage?
In Stevenage, 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.
How long does it take?
Typically 3 to 6 weeks on site.
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.
