Isotherms of sorption and desorption of water vapour by thermal insulating mineral wool products

Isotherms of sorption and desorption of water vapour by thermal insulating mineral wool products were experimentally studied by an exsiccation method. The experimental values of the equilibrium moisture content of mineral wool products, investigated in the range of relative humidity of 0-97% at the temperature of (20 +/- 2)degrees C, are represented by a two-constant empirical formula with constant coefficients b(0) and b(1), depending on the properties of material. The effect of the density of mineral wool products on their equilibrium moisture content is shown. The value of the sorption hysteresis of mineral wool products was determined in the range of relative humidity of 40-90%. The dependence of sorption hysteresis on the density of the products was approximated by the empirical regression equation. The use of sorption hysteresis for computing the equilibrium moisture content of mineral wool insulation at the stage of its drying in building enclosures is demonstrated.