During the service life of buildings, natural ageing of materials due to different chemical, physical, and biological processes can take place. Biodeterioration is important critical factor for durability and usage of different material. Level and duration of moisture stress connected with temperature are the most critical factors for the durability and life time of building materials. For mould development, the minimum (critical) ambient humidity requirement is shown to be between RH 80 and 95 % depending on other factors like ambient temperature, exposure time, quality and surface conditions of building materials. These factors are studied and modelled at VTT Building and Transport. The risk of mould growth in the model is presented as a mould growth index reflecting the amount of mould mycelium on the surface of materials. The index makes it possible to analyse the critical conditions needed for the start of growth, but it is also a tool to measure the progress of mould growth in different conditions and structures. Numerical simulation makes it possible to evaluate the risk and development of mould growth on the surface of wooden material in different structures. For decay development and serious problems to achieved in the buildings, moisture content combined with materials properties, temperature conditions and time are the most important factors. The moisture content for decay development is higher than that for mould growth. The decay development model is based on the mass loss caused by decay fungus in the wood material and the model will give a tool to analyse the decay risk and time needed for different decay rate in different humidity and temperature conditions. In this paper the requirements to numerically simulate mould growth and decay development will be studied. Some analysis about the risks of mould growth in applications with different materials and moisture load conditions are presented.
|Title of host publication||Proceedings of the 2nd International Symposium ILCDES 2003, Integrated Life-time Engineering of Buildings and Civil Infrastrucures|
|Publisher||Suomen Rakennusinsinöörien Liitto RIL|
|Publication status||Published - 2004|
|MoE publication type||B3 Non-refereed article in conference proceedings|
|Event||2nd International Symposium on Integrated Lifetime Engineering of Buildings and Civil Infrastructures, ILCDES 2003 - Kuopio, Finland|
Duration: 1 Dec 2003 → 3 Dec 2003
|Conference||2nd International Symposium on Integrated Lifetime Engineering of Buildings and Civil Infrastructures, ILCDES 2003|
|Period||1/12/03 → 3/12/03|
Viitanen, H., Ritschkoff, A-C., Ojanen, T., & Salonvaara, M. (2004). Moisture conditions and biodeterioration risk of building materials and structure. In Proceedings of the 2nd International Symposium ILCDES 2003, Integrated Life-time Engineering of Buildings and Civil Infrastrucures (pp. 151-156). Suomen Rakennusinsinöörien Liitto RIL.