The humidity of room air is a necessary influence of design under the aspects of thermalbehavior, technology and conservation.The moisture absorption in the walls through sorptive materials or dehumidification on thecold window surface by dew point condensation is low because of the new thermalcharacteristics of these components.The moisture load of a room briefly or also continuously, caused by technological processesor the users cant be compensated.Today, the walls are used like a floor heating system.