20 July 2026

What does a dormer cost in 2026?

All guide prices in one place: prefab uPVC, bespoke wood and renovation — plus the factors that decide where you land in the band.

A prefab uPVC dormer in 2026 costs on average € 6,500 to € 11,000, installed. A bespoke wooden dormer starts around € 10,000 and runs to € 20,000 or more for large widths or special finishes. Width is by far the biggest price factor: every extra metre means more structure, more window frame and more finishing — although the price per metre actually drops slightly as the dormer gets wider.

Beyond width, five things drive the price: the material (prefab uPVC is cheaper than bespoke carpentry), the window frames and glazing, the crane access needed to lift a prefab dormer into place, a possible building permit with its fees, and the region — Randstad rates typically run 10-20% higher.

Already have a dormer that looks tired? Renovation costs € 1,500 to € 6,000 and is almost always cheaper than replacement: weathered cladding, fascia boards and side panels are renewed — often in low-maintenance uPVC — and frames or glazing can be done in the same visit.

Always request multiple quotes: for exactly the same dormer, differences between companies run into thousands of euros. Set every quote against the price index and check whether installation (crane), interior finishing and VAT are included before you sign.