Review of mould prediction models and their influence on mould risk evaluation

A reliable prediction of mould risk in buildings is important to ensure a healthy environment and to avoid social and economical damage. Whereas previously the temperature ratio was often used to minimize the mould risk, nowadays– more advanced – mould prediction models can be found (e.g. isopleth systems, biohygrothermal model, ESP-r mould prediction model, empirical VTT model). These models include the main influencing factors for mould growth: the surface temperature and relative humidity. However, they are based on either experiments or assumptions and some of them neglect a third important influencing factor: the exposure time.The current paper gives an overview of the different existing models and analyses the impact of the mould prediction model on the mould risk evaluation. To do so, the existing mould prediction models are used to predict the mould risk for different temperature and relative humidity courses. The mould risk, the time until mould growth starts and the mould intensity according to the existing prediction models are compared. Based on the obtained results, the influence of simplifications or shortcomings in the mould prediction models is discussed.

► An overview of the existing mould prediction models is given.
► The models are compared and shortcomings, contradictions, highlighted.
► We compare the mould models for stepwise relative humidity and temperature cycles.
► Different conclusions depending on the model used are found.