Roof Windows in Ireland — Velux, Keylite, and Fakro, Cost and Where to Use Them
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Roof window (Velux): €1,200–€2,500 installed. Cheapest daylight on a 1½-storey house. Cheaper than a dormer.
Roof windows (Velux, Keylite, Fakro) in Ireland: €1,200–€2,500 installed per window, including flashing. Cheapest daylight on a 1½-storey house. Far cheaper than a dormer (€5,000–€15,000 each). Standard sizes: 550×980 mm, 780×980 mm, 940×980 mm, 1140×980 mm. Centre-pivot or top-hung. U-value 1.0–1.4 W/m²K for double-glazed; 0.7–1.0 for triple-glazed. Most self-builds use Velux (the most common brand, broadest range). Keylite is a UK/Irish brand with a slightly cheaper price point. Fakro is a European brand with good technical specs. All three have similar U-values and lifespans.
When this matters most
You're at design stage and need daylight in a stairwell or upstairs room.
When this doesn't apply
You've already specified the roof windows.
Sources
Velux Ireland, Product range and prices. https://www.velux.ie/
Building Regulations 2023, TGD-L. https://www.gov.ie/
Frequently asked questions
How much does a Velux cost in Ireland?
€1,200–€2,500 installed per window, including flashing. Cheaper than a dormer. Triple-glazed is €300–€500 more than double-glazed.
What is the cheapest way to add daylight upstairs?
Roof window (Velux). €1,200–€2,500 installed. Cheaper than a dormer (€5,000–€15,000 each) and easier to install.
Velux, Keylite, or Fakro?
Velux is the most common in Ireland, broadest range. Keylite is a UK/Irish brand, slightly cheaper. Fakro is a European brand, good technical specs. All three have similar U-values and lifespans.
When this matters most
You're at design stage and need daylight in a stairwell or upstairs room.
When this doesn't apply
You've already specified the roof windows.
Where to go next
Next decision
The next step in your build sequence.
Branch into
Adjacent decisions at the same stage.
Watch out for
Common mistakes, hidden costs, gotchas.
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