The overarching objective of this study is to develop the numerical model based on logistic equations that predict fungal proliferation and colony forming by taking into account the influence of moisture, temperature and surface characteristics of building materials for various fungi. Toward this end, this paper provides the results of fundamental experiment which measure the responses of fungal mycelium length and colony size on culture media under various environmental conditions. The characteristic of this experiment is to make the suspension that strictly controls the density of the spores, and to execute both the mycelium growth experiment on glass plate and the colony formation experiment on culture media with the same slurry of fungal spores. We focus on humidity effect on fungal growth and mycelium lengths were directly measured by using the digital image data with the microscope that had been taken a picture every 24 hours. Obvious humidity dependence of fungal growth was confirmed in this experiment. In this research, we propose the fungous growth model based on a logistic expression and reports on the result of doing the fitting of the model coefficient by using the experiment data. The results of fungal growth model by logistic expression were in reasonable agreement with the experimental data.
