ABSTRACT
The most common single cause of building deterioration is dampness, and it has been estimated that over 1.5 million dwellings in the UK are seriously affected by dampness problems. The principal sources of dampness are rainwater penetration through roofs and external walls, rising damp through walls and solid floors, and condensation. Because its causes and prevention are different from those of other sources of dampness, condensation is dealt with separately. Owing to the increased humidity created through modern cooking and heating devices and reductions in natural ventilation, condensation is responsible for a large proportion of dampness and mould growth. The sources of moisture can come from inside or outside the building, and it is essential that proper investigation is undertaken to determine the cause of dampness before any remedial action is taken.
