Consideration of the Material Humidity Increase and Conditions of Mold Appearance in Thermally Insulated Buildings

In order to complete the analysis of the water vapor diffusion problem, as well as the conditions for the appearance of mold, the paper investigates the cases when condensation occurs in the layer inside the structure while considering the increase in the humidity of the material in relation to its natural humidity. Additionally, the level of the average monthly humidity in relation to the critical relative humidity, as well as the temperature factor are investigated. The analysis was done on two materials that are most often used in our region – lightweight concrete (Siporex) block and normal concrete, in situations when thermal insulation is laid on the outside or on the inside of the structure. The calculation showed that for certain situations, already after a couple of years, the total humidity of the material exceeds the permitted values for the materials in question. It was also observed that in the case when moisture diffusion occurred adjacent to the insulating material, the total amount of condensed moisture exceeded the permitted value for which the appearance of mold is avoided.