specialists in all aspects of commercial & domestic damp proofing & dry lining

Rising damp is a common problem in older properties either because no damp proof course (DPC) was provided at the time of building, or because a physical membrane has failed or been 'bridged'. In the majority of cases the provision of a remedial DPC is a cost effective and minimum disturbance option.

What is damp?

Dampness in buildings if left untreated can lead to structural deteriation; it will result in decay of timber, spoil decorations and can have problematic health effects through the development of moulds and mites.
When an absorbant material such as paper, wood, cloth or brick is placed in a damp atmosphere it will absorb moisture. If the humidity changes the moisture content of the material will change with it.

Wet wall, dry air

The air is unlikely to be at the above  RH if the damp is caused by water from another source such as rising or penetrating damp. If the wall is wet, it wil be loosing moisture to the air through evaporation all the time. However, constant water rising through the masonry will cause damp patches, salt marks along with associated mould and fungal growth. Typically this is caused by the absence, failure or bridging of the damp proofing course.

Salt contamination due to rising damp.

The source of rising damp is the soil or subsoils which are always wet. Soils consist of biodegraded plant matter hence water in soils is nor pure and usually contains nitrate and chloride salts. These rise through the masonry and are left behind as water evaporates. Rising damp over a number of years can cause high levels of salts in masonry. These residual salts are hygroscopic, hence they contribute to the problems found.

Rising damp results from the capilliary action of water from the ground. In the absence of an adequate DPC  a zone rising to around 50cm (or more) above the skirting level along the whole length of the wall  will result. Where the DPC is damaged or breached, patches of dampness may occur.

Damp Proofing Treatment

Initially the Damp Proofing Course needs to be renewed. Top Joints Dry Lining can provide the Instalation of an industry leading  range of BBA Apporved remedial Damp Proofing Course Creams. Once treated it is necessary to remove and replace the plaster to ensure the hygroscopic salts are removed.

The range of Damp Proofing Instalations offered by Top Joints Dry Lining is unique within the field of property restoration. Our products are as diverse as the famous Lectros (electro-osmotic) system, which works by reversing the background charge differential in damp walls, to chemical DPCs such as Injection Mortar (cementitious grout) and Microtech PI (microemulsion pressure injection).

At the cutting edge of Damp proofing product development in this field comes Ultracure - a diffusion cream system for all types of walls. Our chemical DPC system is suitable for use in accordance with BS 6576 and are manufactured under  ISO 9001 (2008) QA scheme. Injection Mortar and all pressure injection DPC systems are approved by the BBA