In accordance with the requirements and the level of humidity, fans discharge the exhaust air from the bathroom, kitchen, toilet or washroom into the open or into exhaust air shafts. These fans run permanently, thereby creating negative pressure. As a result of this negative pressure, fresh, filtered air flows through the outer wall air vents into the living room and bedroom, children's rooms and work rooms. Particular attention is paid to humidity-regulated home ventilation. By means of this ventilation system, significant losses of ventilation heat can be saved in accordance with EnEV.