Capillary action is a natural phenomenon that is commonly referred to as “rising damp” when applied to buildings. It happens when moisture migrates vertically within structures such as brickwork or masonry to a point where gravity prevents it going any further. It is normally seen as discolouration and plaster degradation from anywhere up to a meter above the floor level. Rising damp should never occur in new buildings, as damp proof courses made from modern plastic materials are incorporated into the wall construction. In older buildings traditional materials such as slate and bitumen hemp were often used, and they can degrade and fail over time, allowing capillary action to ensue. In some instances external ground levels are altered and the damp proof course is bridged, or the wall may not have a damp proof course. These situations can all result in damage caused by rising damp.
There are several methods of damp proofing a wall; some more successful than others. We use just two principal methods at Eradakil, depending upon the application: 1) Chemical injection: suitable in structures of regular size and density, such as coursed brickwork, blockwork, or dressed sandstone masonry. 2) Active Electro Osmosis, which is suitable and effective for application within random mixed masonry structures, when the size and density of individual stones, joints and beds cannot be accurately determined.
Re-plastering is an important part of damp proofing treatment, as hygroscopic salts that have migrated into the plaster during the capillary action process will absorb atmospheric moisture, causing the wall to remain damp even after the new damp proof course has been installed.
We can help you with the assessment and condition of your walls, and the most appropriate method of remedying the problem. Eradakil Limited are members of GPI (Guarantee Protection Insurance) and CGS (Construction Guarantee Services) who administer and issue Independent Insurance Policies to cover damp proofing projects.