How Much Do Building Regulations Fees Cost in the UK?
Building regulations approval is a separate legal requirement from planning permission. It ensures that buildings are safe, energy-efficient, and accessible, and applies to the vast majority of structural building work — even when no planning permission is needed. Fees are charged by either the local authority building control team or a private approved inspector, and are based on the estimated cost of the works.
Typical Cost (UK, 2026)
All costs are indicative estimates. Obtain at least 3 quotes from qualified builders. Prices exclude VAT (20%).
Factors Affecting the Cost
Project value
Most building control fee schedules are banded by the estimated cost of construction works. Higher-value projects pay higher fees.
Application route
Full Plans application requires submission of detailed drawings before work starts. A Building Notice (for smaller works) is simpler but carries more risk if the work does not comply.
Building type
Domestic work (houses and flats) is generally cheaper than commercial or mixed-use buildings.
Council vs approved inspector
Private approved inspectors (now called Registered Building Control Approvers) are often faster than local authority building control and may charge slightly less for straightforward domestic work.
Cost Breakdown
| Item | Basic | Mid-range | High-end |
|---|---|---|---|
| Small extension up to 40m² (Full Plans) | £800 | £1,000 | £1,400 |
| Small extension up to 40m² (Building Notice) | £700 | £900 | £1,200 |
| Loft conversion | £700 | £900 | £1,400 |
| Garage conversion | £400 | £550 | £750 |
| Porch under 30m² | £200 | £300 | £450 |
| New build house | £2,000 | £3,500 | £5,500 |
Costs are indicative and exclude VAT. Regional variations apply.
Typical Timeline
Full Plans decision: 5–8 weeks; Building Notice: work can start 48 hours after submission
Frequently Asked Questions
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