Rising dampness is the capillary rise of water within a wall’s masonry pores. Brick, stone and mortar are all susceptible and the degree of dampness will vary depending on the size of the pores, wall thickness and the level of the water table. It is actually the hygroscopic salts carried to the wall surface which causes visible internal problems. These nitrate, chloride and sulphate salts absorb atmospheric moisture resulting in the breakdown of decorative finishes and plasters.

A thorough survey is always crucial to establish the source of dampness. Frequently, dampness is the result of condensation or poor maintenance. If however the dampness cannot be controlled by lifestyle changes or building design adaptations, we generally recommend two routes:

• A Dryzone cream damp proof course followed by re-plastering with Stonehouse Premix No. 5 plaster and Pro-proof R additive
• A 3mm cavity drain membrane system which creates a physical barrier. This method is ideal for listed properties where the fabric of the building should not be compromised

Often the most effective treatment of controlling rising dampness is through the correct installation of a damp-proof course. Stonehouse uses the Dryzone system which is a damp proofing cream introduced at intervals into pre-drilled holes in the mortar course. It is not injected under pressure and allows the solution to slowly diffuse into the wall fabric, lining the masonry capillaries and reducing the level of moisture rise.