The term Rising Dampness’ is used to describe the vertical movement of moisture through masonry that has no physical barrier to dampness and that is standing in water or damp spoil.

For rising dampness to occur, there must be a supply of moisture at the base of the wall. When rising dampness occurs, the ground moisture rises up through the masonry bringing ground salts i.e. Chloride and Nitrates that migrate up through the damp masonry and migrate out onto the surface of the wall. As evaporation occurs the low-concentration salts become concentrated near the surface and will crystalise out. Chloride and Nitrate salts are ‘hygroscopic’ and will attract moisture from the atmosphere, keeping the surface of the wall damp in conditions of high relative humidity.

If rising dampness is diagnosed and remedial works are undertaken it is an integral part of the remedy that the renewal of the internal wall plaster is carried out. Timbers that are in contact with damp masonry should be considered as ‘suspect’ and should be exposed and inspected for signs of decay.

During the ‘drying out’ process ‘efflorescence’ sometimes occurs. Efflorescence is a white powder-like substance on the surface of the wall and is a sign of drying out.

Under optimum drying conditions it will take approximately 1 month per 25mm thickness of wall to dry out.

Essex and Anglia Preservation are a family owned and run company established for over 60 years. We pride ourselves on a top quality prompt service by qualified surveyors and technicians. We are remedial specialists whose services cover damp proofing to timber treatment. We are based in Essex but cover the whole of the south east UK including Romford, Chelmsford, Colchester, Stansted, and across Essex.