Moisture buffering and effect of ventilation rate and volume rate of hygrothermal materials in a single room under steady state exterior conditions

In this paper, experiments and simulations investigating the moisture buffering of the gypsum boards are described. A test chamber was used for the experiments. The gypsum board was installed on the interior surface in the test chamber. This chamber was located in a climate chamber. The ambient condition of the chamber was controlled at constant temperature and humidity. In the experiment three cases of ventilation rate, no ventilation, 1.0 air change per hour and 5.0 air changes per hour, were investigated. In the experiment the relationship between moisture buffering and volume rate of the materials, various area and locations of the gypsum boards on the surrounding walls were investigated. Simulation studies were also carried out to compare with the measurement results. Experimental data sets for boundary conditions, ventilation rate, amount of moisture production, ambient air temperature and humidity, were provided as input data for simulations. Six simulation programs were used in this project. Simulation results in some of the cases showed comparatively good agreement with the measurement results. However, deviations between experimental values and simulation results in other cases were large.