Rising Damp (Salt Damp)
Rising damp (or Salt Damp, as it is known in many parts of the world) is not the most common form of dampness encountered in buildings; this is left to condensation. However, a high proportion of older buildings are affected by rising damp to some degree or another, as shown in the graph below:
Rising damp in buildings occurs when water from the ground rises up through the bricks and mortar of a building by a process loosely termed as "capilliarity." In simple terms, the water rises up the wall of a building in the same way that oil rises up through the wick of a lamp.
The height to which the water will rise depends on several factors including pore structure of the bricks and mortar and the rate of evaporation. Masonry containing a high proportion of fine pores will allow the water to rise higher than a coarse pored material.
Ground Water and Hygroscopic Salts
 Ground water contains soluble salts, the most significant of which are chlorides, nitrates and sulphates. When rising damp occurs, these pass with the water up the wall and are left behind when the water evaporates. Over many years of active rising dampness large quantities of these salts accumulate within the masonry and decorative surface, most becoming concentrated in a general ‘salt band’ towards the maximum height of rise as illustrated in the diagram on the left. Both chlorides and nitrates are usually hygroscopic, (i.e.they can absorb moisture from the surrounding environment) and, in general, the greater the amount of salts the greater the absorption of moisture - especially under humid conditions. Thus, even though rising dampness may have been controlled by the insertion of a remedial damp-proof course these salts alone can cause the wall and any contaminated decorations to remain damp. It is for this reason that specialist replastering is such an important aspect of rising damp treatment. Further information on replastering as part of a rising damp treatment strategy can be found on our Renderguard Gold product page.
Treatment of Rising Damp
Treatment of rising damp (known as "damp-proofing" or "dampcoursing") typically involves the installation of a chemical DPC, such as Dampcheck Plus using specialist injection equipment, followed by replastering using a salt retardant additive such as Renderguard Gold. However, with the introduction of Dryzone Damp-proofing Cream, the process has now been simplified. The Dryzone system is based on a high-strength damp-proofing cream that is injected into holes in the masonry without the need for an injection pump.
Rising Damp in Floors
Rising damp through solid floors should be treated using our Oldroyd Xs Flooring Membrane or ECS epoxy floor coating.
Free Damp-Proofing Book
 The identification and treatment of rising damp is dealt with in full in our free publication, "Rising Damp and its Control" which can be downloaded free of charge in PDF format by clicking on the image to the left.
The book looks at how to correctly identify rising damp and goes on to describe a treatment strategy using Dryzone damp-proofing cream.
Dryzone damp-proofing cream can be specified under the following clause:
Visit our case studies page for a complete list of case studies available on this website.
Safeguard currently offer the following RIBA-Approved CPD Seminars free-of-charge to architects and specifiers on the UK mainland:
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Rising Damp 
