Building & home improvement cost guide
Garage Conversion Cost Calculator UK
Estimate garage conversion costs by internal floor area, finish and UK region before comparing building quotes. These figures are planning guidance rather than a supplier quotation.
Example for an 18 m² garage with a standard finish in Norfolk or Suffolk.
Adjust it for your project
JobPrice uses a £1,500 per m² baseline with a minimum project allowance, then adjusts for finish and UK region.
Calculate my garage conversion costWhat changes the price?
- Floor levels, damp protection and insulation
- Replacing the garage door with a wall and window
- Heating, electrical and plumbing additions
- Internal doors and connection to the house
- Planning and building-control requirements
Before comparing quotes
- Confirm insulation and damp-proofing standards.
- Check whether utility alterations are included.
- Ask who manages building-control inspections.
Compare the same scope, specification and exclusions across every quote. Keep a contingency for changes and hidden conditions.
How to build a reliable garage conversion price
JobPrice uses a £1,500 per m² baseline with a minimum project allowance, then adjusts for finish and UK region.
Use measured quantities and a written specification, then compare the same inclusions, exclusions and finish level across every contractor quote.
Method note: JobPrice benchmarks are broad planning models, not live supplier quotes. Confirm current local rates, tax, regulation, access and the final specification. Read the full pricing methodology.
How is the garage conversion estimate calculated?
JobPrice uses a £1,500 per m² baseline with a minimum project allowance, then adjusts for finish and UK region.
Is this garage conversion range a final quote?
No. It is an early planning range. A final quote should use the exact scope, current local rates, applicable tax, access conditions and any legal or professional requirements.
How can I get a more accurate garage conversion price?
Use measured quantities and a written specification, then compare the same inclusions, exclusions and finish level across every contractor quote.