Today, one of the most universal types of lining, in terms of the value for money, is rightly believed to be suspended facade systems. Ventilated facade is characterized by the presence of the vertical air gap. If the system has been installed with violations, unventilated areas appear. Insufficient ventilation leads to decreasing heat-shielding properties of the structure. It has to be clearly understood how the ventilated air gap works and how its width affects the performance of the entire system. If the dependence between the size of the channel (height L and width h) and the average speed of free-convective flows is determined it is possible to choose an optimal width of the air gap. This will allow the system to work as efficiently as possible and thus pay off the costs related with installation of the system. The aim of this work was to enhance the structure of the ventilated facade, find methods to define a hydraulically optimal air gap and estimate savings for the system with maximum efficiency. As a result it has been proved that it is reasonable to apply a hydraulically optimal facade.