Comparison of moisture buffering properties of plasters in full scale simulations and laboratory testing

Abstract

The regulation of indoor relative humidity is a key factor for the provision of occupant health and comfort. Passive humidity regulation is possible if porous materials, for example clay and gypsum plasters, are exposed to the indoor environment. Materials that are highly hygroscopic can help regulate relative humidity levels through their capacity to adsorb and release water vapour from and to the indoor air via a dynamic process referred to as moisture buffering. Laboratory test methods have been developed to measure this moisture buffering capacity, which are well-suited for comparative testing of relatively small material samples under controlled conditions. However, quantification of the impact of hygroscopic materials in real buildings requires additional evaluation, like field testing and the support of simulation models, which can successively be used for the development of new protocols capable of giving information about materials’ moisture buffering performances indoors.