Bio-susceptibility of Materials and Thermal Insulation Systems used for Historical Buildings

Several indoor insulation systems based on ecological materials as cellulose, perlite, wooden softboard and reed board with loam, were tested for their susceptibility against fungi under natural- and laboratory conditions. Fungal growth was evaluated by cultivation- and molecular methods. The materials showed a different bio-susceptibility: whereas insulations made of wood and reed with loam had high cell counts, perlite did not show any fungal growth. Therefore, from the microbiological point of view, plaster and board made of perlite are most suitable for thermal insulation. Furthermore, for future applications we suggest a DNA-extraction protocol for microbial ecology studies of construction materials.