How much does it cost to add a dormer window in the United Kingdom?

Refresh Renovations12 Sep, 2025Real Estate

Adding a dormer window in the UK typically costs between £20,000 and £45,000, depending on size, roof type and internal finishes. Structural work and planning applications form the bulk of the cost, while higher-end insulation, windows and bespoke finishes raise the final figure. Always factor in contingencies of 10-15% for unexpected expenses.