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S. Korjenic, A. Kolbitsch:
"Prevention of Mould growth in Dwellings - Diagnostic and Rehabilitation Approaches";
Talk: 1st CENTRAL EUROPEAN SYMPOSIUM ON BUILDING PHYSICS, Cracow - Lodz; 2010-09-13 - 2010-09-15; in: "Research on Building Physics", Technical University of Lodz, Faculty a/Civil Engineering, Architectllre and Environmental Engineering. Poland, Proceedings of the Is1 Central European Symposium on Building Physics 13-15 September 2010, Cracow - Lodz, Poland (2010), ISBN: 978-83-7283-367-9; 545 - 550.

The aim of this evaluation was based on the results of a series of measurements taken in buildings in Austria. In recent years, damage due to mould from moisture infiltration in buildings has significantly increased. Despite better thermal insulation, the number of apartments with mould has been continuously increasing. Scientifically, many questions regarding mould in buildings are not yet sufficiently explained. There is still no answer to the difficult question: "How can damage caused by mould be registered systematically and uniformly?" The damage is often the result of several contiguous causes. Also, the extent of the health impact of mould pollution is unclear and many open questions remain. The most significant cause of mould growth in residences is the presence of high humidity which can be traced back to construction defects or incorrect user behaviour. High thermal insulation standards are politically important and ecologically useful for the reduction of energy consumption. If air tightness of windows is improved, thermal transmission and ventilation losses are reduced. The consequences of a lower air change rate leads to increased concentration of air pollutants and higher air humidity. Higher humidity levels associated with increased concentrations of air pollutants have been observed to affect mould growth not only in renovated buildings, but also in new buildings. However, the fact that warmer interior surface temperatures result from increased insulation contradicts the increase of mould damage. Correctly constructed buildings and user behaviour have to be combined in order to keep an apartment free of mould. The results suggest that in most relevant cases, mould growth is due to poor construction detailing in highly insulated airtight buildings and not because of thermal insulation or ventilation. The different causes are due to a insufficient damp-proofing, improper installation, thermal bridges, high internal moisture production, and occupant behaviour which does not react to alleviate high moisture levels.

mould, moisture, air humidity, thermal insulation, ventilation