Rising damp control
The destructive effects of rising damp
Rising damp is a very genuine problem but is widely misunderstood. It is also frequently mis-diagnosed where it does not exist at all.
The majority of buildings constructed in Cornwall before around 1900 were not built with any form of damp-proof course (DPC) at the base of the walls, and many have sustained some degree of rising damp which affects only the lower parts of the walls. True rising damp is relatively uncommon in buildings constructed after the Victorian period, however existing damp-proof courses are occasionally “bridged” by higher external ground levels or solid floors, with similar effects to actual rising damp.
The usual remedy is to remove the salt contaminated internal plaster, install a remedial damp-proof course to prevent or control further rising damp, and then to replaster the walls using a system designed to withstand the effects and migration of the residual salts and associated hygroscopic moisture.
Chemical DPC systems
We use a range of BBA Approved liquid and gel based systems to prevent or control rising damp. These are installed at the base of effected walls via a series of small holes drilled into the masonry. Liquid DPCs are usually installed using low-pressure injection or irrigation methods to treat the intended course of masonry, whilst the more concentrated gel systems are designed to diffuse slowly into the substrate.
Electro-osmosis
This involves the introduction of a low static electrical charge into the masonry, via a series of titanium wire anodes installed into the base of the walls and connected to a mains electrical circuit via a small transformer. This static charge interferes with the surface tension which is essentially responsible for creating capillary action, and thereby eliminates any further rising damp.
