Rising damp (structural)

From Wikipedia, the free encyclopedia

Rising damp refers to the vertical flow of moisture through the masonry wall structure of a building. Water rises through walls due to capillary action.

Modern houses include damp-proof course to act as a barrier through which water cannot pass, thus helping to prevent rising damp.

Rising damp tends to cause secondary damage to a building. The unwanted moisture enables the growth of various fungi in wood, causing rot. Plaster and paint deteriorate and wallpaper loosens. Stains, both from the water and from mold, mar surfaces. Externally, mortar may crumble and salt stains may appear on the walls. Steel & iron fasteners rust.

This problem is mainly related to older structures because no water proof barrier was placed between tiers of masonry.

There is a good deal of controversy surrounding the diagnosis of rising damp, with evidence that only a tiny percentage of damp houses are suffering rising damp, despite the high level of positive diagnoses. Some believe the profit motive to have more to do with these diagnoses than sound science.