Water vapor permeability of building materials : improved analysis of dry cup experiment

Water vapor permeability of building materials is usually measured using dry cup experiment according to the ISO 12572 standard. For this test, suitable adsorbing desiccant should be used to provide stable low vapor pressure conditions within the cup. However, previous measurements on permeable materials have shown that boundary conditions within the cup are not equal to 0 %RH and not constant over time. The aim of this paper is to extend this finding on other less permeable building materials. Peer-review the responsibility of the of the ICMB21.