Using state-of-the-art computer-simulation programs developed at the University of Berkeley, California, all Optiwin windows and doors are hand-crafted and precision engineered.

A difference you can feel.

Unique Optiwin features include:

- airtigt, super-insulated window

- two seals, not one

- wood/cork/wood construction

- first heat energy-producing window in the worldl!

As certified by the Passivhaus Institute in Germany - the ultimate, European standard for building energy-efficiency - Optiwin windows are the only ones in the world to maintain ambient room temperature on the surface.