Windows for Passivhaus and EnerPHit projects

Timber-clad low-energy house with deep-set windows and external shading

Passivhaus and EnerPHit projects typically need installed whole-window U-values of 0.85 W/m²K or lower, which means triple glazing, warm-edge spacers, insulated frames and airtight installation. The window is modelled in PHPP with its frame, glass, spacer and installation values, so the data matters as much as the product.

What the standard asks of windows

Passivhaus targets very low heating demand. Windows are the weakest part of the envelope, so they are specified for low heat loss and good solar gain where the sun reaches them, and installed so that the joint between frame and wall does not leak heat or air.

Installation position and airtightness

Setting the window in the insulation layer, wrapping it with insulation and sealing it with airtightness tapes keeps the installation psi-value low. These details are agreed with your designer before ordering.

Solar gain and overheating

South glass can use a higher g-value unit to capture winter sun; east and west glass may need shading to avoid summer overheating. That balance is done in the energy model.

Certified components

Passive House Institute certified windows simplify certification. We price certified systems on request and provide the values your designer needs.

Questions

Do I need certified windows for Passivhaus?

Not always, but they make certification simpler.

Is triple glazing enough?

It is the starting point; frames, spacers and installation all count.

Sources

BRE: is triple glazing better than double?

More guides

Get a free survey and quote

Free survey · written quote, no obligation