RISING DAMP

Rising Damp is called “Rising Damp” because the moisture starts at the base of the wall and moves slowly upwards. 

Water rises up the wall by capillary action through the brick or blockwork to the point where evaporation occurs. As the dampness evaporates from the wall into the atmosphere, the salts that had been diluted by the water will accumulate in the surface layer of the masonry –  the first point where the dampness evaporates (usually the first 10mm at the base of the wall/just above your skirting boards). 

As salts accumulate within this shallow depth of masonry, the pores of the masonry become more and more blocked with salts which slows down the evaporation.

As time passes, the salts continue to damage more and more. Before you know it, 10mm becomes 20mm and so on. The salt damage will keep rising up the wall until the weight of the water has enough downwards force (from gravity) that the water cannot rise any higher. 

From this point on, the dampness will continue to evaporate from the already salt-affected areas, accumulating to the point that the surface of the masonry eventually crumbles to dust! This is generally not a quick process but it can be absolutely devastating to a home. After years of this silent killer developing, the rising damp will become a structural issue and the cost of repairing this can be quite high. This is the kind of thing you want to have fixed sooner rather than later.