Gravity ventilation is the simplest and oldest way of exchanging air in buildings, which consists in the construction of vertical ventilation ducts that discharge warm air from the upper part of the room to the outside.
Thanks to the pressure differential is created in the ventilation chimney (under certain atmospheric conditions), where a draft of air is created by which the air is extracted by the ventilation duct through the chimney upward. However, this situation only occurs in strictly defined circumstances.
No mechanical device neede
