UK cost calculator

Loft Conversion Cost Calculator

Compare Velux, dormer, hip-to-gable, mansard and bungalow conversion budgets using current 2026 UK benchmarks.

Conversion type

Approx. new floor area (m²)

UK region

Include new ensuite?

Estimated project range

£37,600 – £56,400

Typical planning estimate £47,000. Benchmarked to 2026 UK loft-conversion ranges; size scaling and regional adjustment are UK Home Costs modelling assumptions.

Benchmark source: Checkatrade 2026 loft conversion cost guide. Regional and area adjustments are UK Home Costs modelling assumptions. See sources →