"Electro-physical" methods to stop rising damp

Abstract

Rising damp is a recurrent hazard to ancient buildings and its relevance is expected to increase in future, due to climate changes. In spite of the large diffusion of methods and products to stop rising damp, scientific literature on their effectiveness in the field is often scarce and not conclusive. This is particularly true for recent solutions; examples are the “electro-physical” methods, which are currently flourishing in many countries. These methods are often lacking a scientifically based proof of their working principles and effectiveness. Within the JPI-CH project EMERISDA, the effectiveness of two different commercial electro-physical devices was investigated in two case-studies. The devices were positioned in such a way as to include humid walls under the influence of the device as well as humid walls, comparable in orientation and structure, out of its reach, to be used as reference. The effectiveness of the devices was assessed by collection of samples at different heights and depths in the walls and gravimetric determination of their moisture content. Conclusions are drawn on the effectiveness of the methods by comparing the moisture content before and one year after the intervention, taking into account the variation in moisture content in the reference walls.