Dynamic water vapour sorption: measurement and modelling.

The objectives of thisinvestigation were to examine the dynamic water vapour sorption offurnishing materials and to compare the experimental results withpredictions obtained from the Moisture Admittance Model. Dynamic sorption measurementswere carried out for common building materials. The measurements were made by placingspecimens of the materials in a humidity chamber and varying the ambient humidity between46% and 90% RH at constant 22C. The weight of the specimens was monitored in situduring this procedure. The materials included carpet, vinyl strips, MDF, chipboard, parquettiles, plywood, untreated timber and gypsum board. The experiments showed that the dampingeffect of materials on air humidity in daily cycles of high-low humidity is determined by thespeed at which moisture can be absorbed and cannot be predicted by using sorption isothermdata. However, the results were then used to obtain material parameters for the MoistureAdmittance Model (MAM). The investigation showed good agreement between model andexperiment.