01
Plan your conversion
Room ideas, planning guidance and a clearer brief.
Costs
What does a garage conversion cost?
We show a practical budgeting guide to help you understand what affects a garage conversion. Use the calculator for an estimated quote range based on your garage size, finish level and requirements.
01 Professional builder introductions02 Clear cost guidance03 Planning & building control
Practical guidance for UK homeowners02
Get clear pricing
A guide range before you request quotations.
03
Build with confidence
Know what to ask about scope, approvals and warranty.
| Project shape | Guide range | What it may include |
|---|---|---|
| Standard single garage · 6m × 3m | £15,500–£20,500 | 18m² guide area, insulation, floor, plastering, electrics, heating and standard finishes. |
| Standard double garage · 6m × 6m | £30,500–£41,500 | 36m² guide area, with the same standard-room assumptions across the larger footprint. |
| Enhanced single garage · 6m × 3m | £18,000–£23,500 | Higher finish allowance for upgraded materials, joinery or additional specification. |
| Enhanced double garage · 6m × 6m | £36,000–£47,000 | Higher finish allowance applied to the larger 36m² guide area. |
| Plumbing or drainage add-on | +£3,000–£5,000 | Bathroom, utility, kitchenette or drainage work, subject to the existing services and route. |
| New internal partition | +£1,000 | A straightforward new partition within the converted space. |
Size is only the start
A double garage has more floor area, but it may also need a larger structural opening, more heating and more finishes. A narrow integral garage can be harder to lay out than a larger detached building.
Details that commonly add cost
- New windows, doors or structural openings
- Uneven or damp floors that need rebuilding
- Drainage runs for a bathroom or utility use
- Roof, wall or ceiling upgrades
- Restricted access and longer material handling
Use the calculator
Turn the idea into a conversation.
Try different room sizes and finish levels, then take the result into a quotation request.
Open calculatorUseful advice from this page
Keep exploring this topic
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