What does a 3-metre dormer cost?
A 3-metre dormer costs as an indicative range €6,000 to €9,000 including installation and VAT. The spread is driven by material choice (PVC, wood, aluminium), glass (HR++ or triple), insulation thickness, roof pitch, roof height (crane accessibility) and how much interior finish is included. Get at least three quotes and compare line items — not just totals.
Indicative price ranges per width
As an indicative range (incl. installation and VAT): 2 m €5,000–€6,000 · 3 m €6,000–€9,000 · 4 m €7,000–€10,000 · 5 m €8,000–€11,000 · 6 m €10,000–€14,000. These are market indications — not a quote. The exact amount depends on roof pitch, roof height (accessibility), material and finish.
What is included in the price?
A typical quote for a 3-metre dormer includes: load-bearing structure (trimmers, beams), cheeks (plywood or prefab core with EPDM/zinc cladding), the roof element, roofing (EPDM, bitumen or zinc), frames and glass (HR++ or triple), insulation (PIR/PUR or mineral wool), interior trim, ventilation grids, crane hire, VAT and optional scaffolding. Always ask for an itemised quote — a lump-sum total makes fair comparison impossible.
Why do quotes for the same size differ?
Three providers can vary by up to 40% on the exact same width. Causes: prefab vs. traditional on-site build, frame material (PVC, wood, aluminium), glass thickness (HR++ or triple), insulation value (Rc 4.5 or Rc 6.0), cladding colour and type, site accessibility (crane required or hand-carried), and how much interior finish and electrical work is included.
What is usually excluded?
Items often outside the quote: interior work beyond trim (plaster, paint, flooring), electrical (extra sockets, switches), heating (relocating a radiator), shading, curtains or shutters, and repair of any roofing damaged around the work area. Ask each provider explicitly what is excluded.
How to compare three quotes fairly
Lay the three quotes side by side and check per line item (structure, frames, glass, insulation, roofing, finish, VAT) what is mentioned. The cheapest is rarely comparable to the most expensive — often items like insulation or interior finish are missing from the cheapest. Ask the builder for reference projects and read our quote-request checklist.