What does a garage conversion cost in the UK in 2026?
A garage conversion is one of the most cost-effective ways to add usable space to a home.
| Conversion type | Typical cost range |
|---|---|
| Basic habitable conversion (no bathroom) | £7,500–£12,000 |
| Living space or home office (mid-spec) | £10,000–£16,000 |
| Bedroom with en-suite | £14,000–£22,000 |
| High-spec with bifold door | £16,000–£28,000+ |
Add 20–30% in London for the labour premium.
Do you need planning permission?
Most garage conversions are permitted development — no planning application required — provided you are converting the internal space without extending the external footprint. Exceptions: the property is in a Conservation Area and the works affect the external appearance; PD rights have been removed; the garage is on the front elevation in a restricted area; the property is listed.
Building Regulations: always required
Regardless of planning permission, Building Regulations approval is always required for a garage conversion. This covers: structural adequacy; thermal insulation to current standards (Part L); ventilation (Part F); fire safety (Part B); damp-proofing (Part C); electrics (Part P).
Will a garage conversion add value?
A well-executed conversion typically adds 70–85% of the conversion cost to the property value. Key factors: does the property still have off-street parking? Is the conversion genuinely usable? Does it have a Building Regulations completion certificate?