Interface influence on moisture transport in buildings

Moisture damage is one of the most important factors limiting building performance. A moisture measuring device based on non-destructive method of gamma rays attenuation, allows measures to deepen concepts in building physics related to the moisture transfer; study the influence of the interface between layers in moisture transfer; analyse the influence of gravity on absorption and drying of different building materials; study the kinetics of absorption and drying of walls of one or more layers; analyse the importance of the temperature gradient in the movement of moisture; calculate the coefficient of water diffusivity of some building materials. This work presents an experimental campaign and a critical analysis of water absorption in samples of red brick with different densities, with and without joints at different height positions and different contact interface configurations, using two experimental methods (gravimetric method and gamma ray's attenuation). The results show a slowing of the wetting process due to the interfaces hygric resistance. The samples with hydraulic contact interface (cement mortar) present lower absorption rate than the samples with lime mortar. The influence of air space between layers was also demonstrated, i.e., the air space interfaces increase the coefficients of capillary significantly, as the distances from the contact with water increase. (C) 2017 Elsevier Ltd. All rights reserved.