Humidity conditions of the external thermal insulation composite systems with the ventilated air gap

Currently, external insulation facade systems and particularly rainscreen and external thermal insulation composite systems (ETICS) become very popular. Each of mentioned systems has a number of advantages and certain disadvantages due to which the problem of durability and efficiency of external insulation facade systems remains actual. One of the methods to solve this problem is to provide traditional external thermal insulation composite systems with the ventilated air gap presented by innovative material – ventilated façade mat Stuccodrain.

Influence of air permeability of provided ventilated air gap in ETICS on moisture conditions of the wall structure has been considered in this work. The method of calculation of such an influence is based upon the comparative evaluation of non-stationary humidity conditions of ETICS and humidity conditions of ETICS with the ventilated air gap.

The results of the comparative evaluation show that humidity of render layer in case of ETICS provided with ventilated air gap reduces significantly in comparison with traditional ETICS. Humidity reduction in external render layer of structure raises the durability and keeps the efficiency of the structure during the exploitation period. At the sections of the ventilated air gap where the humidity level of render layer less then maximum sorption humidity freeze and defrosting of the layer during exploitation in most case will not lead to destructions.