Natural ventilation

Natural ventilation (also free ventilation or aeration rarely ) is the air exchange in buildings by the self-adjusting "natural" buoyancy of different warm air ( chimney effect).

The ventilation driving pressure difference is calculated from the resulting from the temperature difference density difference with the ambient air and the available lift height h Natural ventilation (or natural draft ventilation) was prior to the development of machinery for conveying air (fans, compressors) the only way to Structures specifically to ventilate and came already in antiquity, for example, the Egyptian pyramids, are used. Natural ventilation is now used commercially and used in industrial large buildings, especially with large amounts of heat as in the steel and glass industries and in the construction of so-called cooling towers ( cooling tower in power plant construction ) specifically. In agriculture, there are many stables that are ventilated in this way.

In organic architecture, there is increasing cultural buildings with gravity ventilation. It is thereby possible to substantially dispense with ventilation techniques with an additional power requirement. Well-known examples are the Saalbauten the Waldorf schools in Cologne and Dusseldorf, as well as the gymnasium of the Odenwald School in Heppenheim - Oberhambach or the Prime Tower in Zurich and the Matallarbeiterschule the city of Winterthur.