United States of America
Indoor environmental quality
In commercial buildings
Window vents and ventilation flaps are used to provide a continuous background air exchange in your home. A house needs to breathe to prevent condensation and polluted air. The unique ventilation flap in VELUX roof windows ensures good, draught-free background ventilation and has a filter that keeps out insects. The ventilation flap is ideal in bedrooms, where it enables a light flow of fresh air during the night even with the window closed.
On very cold days, we recommend that you keep the ventilation flap closed.
Background ventilation principles:
VELUX roof windows with ventilation flap
The unique control bar with built-in ventilation allows draught-free background ventilation even when the window is closed.
One more click – and the window is open.
Watch the video