Considering the problem of fungal growth in living quarters, and especially after the buildings have been thermally insulated, learning more about mechanisms determining fungal growth in the conditions of day-today usage of such buildings seems to be a necessity. The research on indoor microclimate influence on fungal growth was carried out for too years in two pavilion type living quarters on a residential estate in built Wroclaw - Brochów. A microclimate fostering fungal growth was modelled in the pavilions. Samples of different building materials were exposed to and infected by fungi, and fungal growth was observed and analysed, with regard to the indoor environment. The paper presents the results of the first stage of the research (30 weeks).