Dormer window replacement cost in Ireland
Replacing an existing dormer window in Ireland costs €450 to €950 per window in white A-rated uPVC, €650 to €1,250 in colour-foiled triple-glazed uPVC or flush sash, and €850 to €1,750 in thermally broken aluminium or alu-clad. A full dormer bungalow (8 to 12 windows) costs €5,200 to €10,500 in uPVC.
Per-dormer and full-house supply-and-fit prices, plus what cheek insulation, lead flashing and new attic dormer construction add.
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Select whether you are replacing existing dormer windows, upgrading a whole dormer bungalow, insulating cold dormer cheeks, or building a new attic dormer.
Estimated supply & fit guide
€1,950 to €5,000
3 to 4 dormer windows at €650 to €1,250 per dormer window (13.5% VAT included)
Guide price to replace 3 to 4 dormer windows within existing dormer openings in colour-foiled triple-glazed uPVC or flush sash. Includes 90-degree Easy-Clean Part B fire-escape egress hinges, dressing existing lead apron flashing and internal reveal trim.
Ask a local specialist for a quoteDormer window prices by job and frame
| Dormer window job | White A-rated uPVC | Coloured triple uPVC / flush sash | Aluminium or alu-clad |
|---|---|---|---|
| Single dormer window replacement | €450 to €950 | €650 to €1,250 | €850 to €1,750 |
| Pair of front dormer windows (2 windows) | €900 to €1,900 | €1,300 to €2,500 | €1,700 to €3,500 |
| 3 to 4 upper dormer windows | €1,350 to €3,800 | €1,950 to €5,000 | €2,550 to €7,000 |
| Full dormer bungalow (8–12 windows) | €5,200 to €10,500 | €6,800 to €12,800 | €9,500 to €17,500 |
| Full dormer bungalow after €4,000 SEAI grant | €1,200 to €6,500 | €2,800 to €8,800 | €5,500 to €13,500 |
All prices include survey, removal of old frames, installation and 13.5% VAT. Insulating and re-cladding the dormer cheeks while the window is out adds €650 to €1,450 per dormer.
Three things specific to dormer openings
- Lead apron tray under the cill: Unlike a ground-floor window that sits on a concrete block cill, a dormer window cill dresses directly over a Code 4 or Code 5 lead apron flashing onto the roof slates below. The fitter must lift and re-dress or seal the cill without splitting the lead.
- Timber stud movement and wind exposure: Dormer boxes project out of the roof slope and take full Atlantic wind loads. Frames must be strapped directly into the doubled-up timber trimmer studs and sealed with flexible airtight foam and compriband tape.
- Mandatory 90° Easy-Clean fire-escape hinges: Every upper dormer bedroom window needs heavy-duty stainless egress friction stays that open to 90 degrees for Part B escape and slide sideways for safe indoor glass cleaning. See casementwindows.ie for casement hinge options.
Real examples and installation detail
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Questions dormer homeowners ask
Is it cheaper to replace the upstairs dormer windows and ground-floor windows together?
Yes. Doing all 8 to 12 windows on a dormer bungalow in one visit (€5,200 to €10,500 in uPVC) saves €800 to €1,500 on separate survey, tower setup and crew travel, and is required if you want to claim the €4,000 SEAI Windows Grant.
How long does it take to replace 3 or 4 dormer windows?
Replacing 2 to 4 existing dormer windows normally takes a two-person fitting crew 1 day. If the dormer cheeks are also being stripped, insulated with PIR board and re-clad, allow 2 days.
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Replacing cold, draughty or rotten dormer windows?
One vetted window company covering your county inspects the dormer frames, lead apron and side cheeks, and gives you a written price.