Water vapour permeability of innovative building materials from different waste

Abstract

The hygrothermal performance of building materials is a very important issue for indoor comfort. The aim of this study is to measure the water vapour resistance factor μ of recycled waste materials. Leather cuttings, rice husk, and coffee chaff were used in order to manufacture innovative panels for thermal-noise building insulation. The permeability measurements were carried out by the dry cup method in compliance with the Standard EN ISO 12572. In the experimental campaign, conventional gypsum plaster and expanded polystyrene were also considered, whose hygrothermal characteristics are known from the Literature, in order to verify the reliability of the method. The moisture transfer properties of the innovative panels are higher than the values available in the Literature for other vegetable and mineral fibers-based panels (sheep wool, wood, cork, expanded vermiculite and perlite, glass or stone wool, and so on). However, the high μ-value obtained for coffee chaff panels (equal to 392) could involve an increase in heat loss and acoustically weak points.