Hygrometric Characterization of New Bio Sourced Materials for Building Construction

Abstract

This paper treats the moisture-related characteristics of bio-based construction materials. Experiments were conducted using the wet cup method and the isothermal adsorption method. This last method provided information on the amount of absorbed moisture by each material, while the wet cup method measured the amount of moisture vapor crossing the material and the moisture resistance of the material. Two different samples were studied and compared: the first one is from a lightweight earth material having a good thermal insulation property. The second one is the cob material characterized by its durability and mechanical structures. By assuming that the absorbed moisture flux is equivalent to the flux passing through the material under steady state conditions, the study was able to calculate transfer coefficients such as water vapor permeability, moisture diffusion coefficient, and ambient transfer coefficient.