Mould growth is a significant problem in the Swedish building stock with the negative consequences concerning health, comfort, and durability of construction. A combination of the climatic conditions and the traditional building constructions and materials, results in vulnerability of Swedish buildings to this problem. A tool supporting design is needed. Confronting stochastic reality (variable climatic conditions, stochastic process of mould growth) deterministic tools seem to be insufficient to relay the decisions upon. Probabilistic model for evaluation of reliability of structure with respect to mould growth based on the up to date developments in the field of deterministic modelling of bio- and physical processes and the new probabilistic software is proposed. The model offers estimation of the probability of performance failure (mould germination on a material) or reliability, using mathematical relationship between probability density functions of the load and resistance parameters. To become a design tool the model should be calibrated, refined and if possible validated. Then it could be used at the design stage to evaluate the risks for different construction/environment systems.
Krystyna Pietrzyk, Ingemar Samuelson, Pernilla Johansson
SP Sveriges Tekniska Forskningsinstitut, Energiteknik, Byggnadsfysik och innemiljö