Capillary condensation redistribution (CCR) test: measurement results of 5 materials and comparison to modelling

Abstract

To improve the accuracy of hygrothermal modelling, a capillary condensation redistribution (CCR) has been proposed to help distribute the share of vapour and liquid conductivity functions based on a wider experimental dataset. This paper aims to provide further data by presenting the CCR test measurement results of 2 calcium silicate (CaSi) boards, 2 aerated autoclaved concrete (AAC) boards and spruce (the latter both perpendicular and parallel to the grain). A variation of the CCR test setup is described. The measurement results agree with those from literature where some of the materials presented here were also tested. Modelling results using previously available material properties are compared to measurement results: none of the AAC and longitudinal spruce material properties can reproduce the moisture content levels achieved in the study, while CCR-optimized CaSi material data is close to the measured results. The best agreement between measurements and modelling of spruce perpendicular to grain are achieved with material properties which discard liquid conductivity and presume increased vapour permeability due to increase of moisture content instead.