Use of moisture-buffering tiles for indoor climate stability under different climatic requirements

Abstract

Indoor humidity is an important factor for human health and well-being or for damage like mold growth. Excessive indoor humidity conditions may be caused by inadequate ventilation or temporarily due to change of temperature in rooms. The moisture-buffering effect of linings and the resulting impact to air humidity are the topics of this study. Specially developed unsealed ceramic tiles and their capability to dampen the fluctuation in air humidity have been investigated, including the determination of relevant hygric material properties. A series of experiments in chambers were designed and executed to show summer and winter situations with temperature changes or different moisture sources. The resulting relative humidity in the chamber was monitored in the baseline experiment with no moisture buffer capacity, as well as in the experiment with the installed new developed moisture-buffering tiles. The experiment was validated and extrapolated to real room conditions using a transient hygrothermal whole-building simulation tool. The results show a reduction of relative humidity fluctuation, which attests to the humidity-buffering effect of the material. The verification of the hygrothermal simulation with the experiment was successful. A hygrothermal whole-building simulation demonstrates the damping of air humidity fluctuations for buildings under real usage condtitions and in diverse climate regions. It is shown that thermal comfort conditions can be improved along with lower energy requirements for dehumidification/humidification by using humidity-buffering linings. A correct assessment can only be conducted with hygrothermal whole-building simulation tools.

Acknowledgments

Florian Antretter is Group Manager Hygrothermal Building Analysis. Christoph Mitterer is Scientist. Seong-Moon Young, PhD, is General Manager (IMA Group Leader).