Reducing the requirements for ventilation heat through natural ventilation of buildings by use of air permeable porous outside walls. Verringerung des Luftungswarmebedarfs bei naturlicher Luftung von Gebauden durch Verwendung luftdurchlassigkeit poroser A

Calculations show that natural ventilation exploiting wind and specific gravity differences may reduce the need for ventilation heat. This is not done as usual by ventilation through open doors and windows but through fine porous air-permeable outside walls. The optimum thickness of the heat insulation layer is defined, giving maximum saving of total heating and ventilation energy.