The wall of straw bundles is a breathing one. Moisture passes out through such a wall. Seeking to strengthen this effect , the outside wall of the building must be stuccoed with the type of stucco, permeable to moisture and air in order to get natural draught outside. Clay plaster also perfectly absorbs moisture. Straw houses are not damaged by moisture, the walls do not steam up. A steam bath can be build from straw bundles as well. The high relative humidity does not make any damage to the walls of the bath. Due to the breathing , the mould and fungus do not occur on the wall.