When it comes to passive houses, you can’t be passive about your choice in windows. Windows and doors are the enemy of an efficient building envelope, since they’re essentially holes in an otherwise super-efficient wall and roof system. Every window choice is a careful balance of performance and aesthetics.

The Ultratherm Ultima is a wood-aluminum composite with three or four layers of glazing.

Enter Bertrand Windows and Doors. With an entire line of windows dedicated to the science of passive home creation, you can’t go wrong. They’re our exclusive partner for a reason— you don’t have just one option, but four to choose from. Three of their products have triple-glazing and a fourth has four layers of glass to provide the highest performance. With a wide selection of wood species, thermally broken aluminum, and composites they have a solution for every passive house fenestration decision.

Bertrand’s windows are crafted in Poland to European high standards.