Passive House Windows in Ireland — U-value, Frame, and What the Certifier Wants

Passive House windows: U-value 0.7–0.8 W/m²K whole-window (including frame). Triple-glazed, timber or alu-clad frame, warm-edge spacer. The Passive House Institute (PHI) in Germany certifies specific window models. Check the certified list before specifying. A 150 m² Passive House has 25–35 m² of windows. Window cost: €25,000–€50,000 installed. The Passive House standard also requires: a psi-value (thermal bridge at the window-wall junction) of ≤0.04 W/m·K, which the architect details in the reveal. Window installation matters as much as the window: a Passive House window installed poorly is no better than a double-glazed unit.

TL;DR

• Passive House windows: U-value 0.7–0.8 W/m²K whole-window. Triple-glazed, timber or alu-clad frame, warm-edge spacer.

• Passive House Institute certifies specific window models. Check the certified list before specifying.

• A 150 m² Passive House has 25–35 m² of windows. Window cost: €25,000–€50,000 installed.

When this matters most

You're building to Passive House standard and need to specify the windows.

When this doesn't apply

You're targeting A1 or A2, not Passive House.

Frequently asked questions

What is a Passive House window?

A window certified by the Passive House Institute with U-value 0.7–0.8 W/m²K whole-window. Triple-glazed, timber or alu-clad frame, warm-edge spacer.

How much do Passive House windows cost in Ireland?

€25,000–€50,000 installed for a 150 m² house with 25–35 m² of windows. Premium cost, but the airtightness and U-value are unmatched.

Where can I find Passive House certified windows?

The Passive House Institute (PHI) maintains a list of certified windows at passivehouse.com. Most major European manufacturers have certified models.

Sources

Passive House Institute, Certified components. https://www.passivehouse.com/