Wind catcher is a device that ventilates a building by the use of wind. A small tower on the roof contains an opening that faces the prevailing wind, which is at a cooler temperature than the interior of the building. Because the wind velocity at this opening is greater than it is at the lower windows of the building, air in the shaft of the tower is forced down the shaft to cool the building.
Wind catchers improve ventilation in areas furthest from the windows. The dampers can be controlled by the Building Management System or manually to regulate the fresh air intake. It can improve the local air speed by about 25%.