Electrical conductivity sensors for water penetration monitoring in building masonry materials

Water penetration in porous building materials can cause damage in building components exposed to wet environmental conditions. A system to monitor water penetration by means of electrical conductivity measurements is presented (Gummerson et al. Build Environ 15:101–108, 1980). The sensor allows non-destructive and continuous monitoring of different layers of building envelopes with high space and time resolution. Capillary uptake experiments have been performed to assess the reliability of the developed system. Sensors data are compared to the results of the analysis of neutron radiographs taken during the experiments. These sensors are easy to apply in different positions, even deep in the structural components where direct gravimetric investigation is not possible. Electrical conductivity measurements provide a good temporal description of the capillary uptake process, however a calibration for moisture content quantification could not yet be achieved.