Effect of indoor climatic conditions on the risk of water vapor condensation and mould growth

The article presents a new approach to determining the risk of mold growth in buildings. To assess this phenomenon, we use the so-called limit temperature factor fRsi calculated based on the assumptions of the ISO 13 788 standard. The innovation is the use of a local climate model to calculate it, i.e., the one that occurs in areas particularly exposed to mold development, i.e., the corners of the building. The article presents long-term field studies of indoor microclimate parameters. They were carried out in a model room, such as a living room, in three groups of buildings differing in the period of construction and the thermal quality of external partitions. Their aim was to determine measurement differences in the profiles of air temperature and relative humidity changes obtained as a result of measuring these quantities in the central part of the room (Ti, RHi) and in the outer corners (T2D, RH2D). The result of the experiment was to determine the mutual relationship (statistical relationship) between the parameters of the internal environment (Ti, RHi) and their local changes (T2D, RH2D) and the development of the socalled local climate model. It was the basis for determining the relative humidity correction in calculating the limit value of the fRsi,max factor for places particularly exposed to the initiation of mold growth, i.e., external corners. The presented research results confirm the need to take into account the non-homogeneous distribution of environmental parameters in the room, especially in the context of relative humidity, as a parameter determining the development of mold.