Current requirements for energy savings lead to improve heat insulation properties of claddings. That is the reason why thermal insulation properties are improved in existing buildings, such as additional insulation of the building envelope and replacing filling holes in the facade. The reason for the implementation of the glazing of these areas is the idea of improving the indoor climate of the living space. It is assumed that condensation of water vapor and occurrence of moulds on inner surface of the structures can happened in certain conditions of indoor air.