Ventilated facades reflect heat from the sun in summer. The façades accumulate the heat on the panels and do not allow it to pass to the lower layers. Heat leaked through the panels is transferred from the wall to the outside thanks to the air gap. (Chimney Effect)Rainwater flows down the panels and 5-8% water enters the joints. Thanks to the air gap, a part of it flows down, the rest evaporates and does not touch the insulation on the wall. (Chimney Effect). In heated buildings, in winter, the vapour pressure inside is generally higher than the outside. This may cause the vapour pressure to be carried along the outer wall. Then, the moisture is removed through the air gap with free flowing air. Some part of rain and snow water entering through the joints, thanks to the air gap (max. 8%) evaporates and some part flows down without touching the wall surface. It does not touch the wall surface or the insulation layer.