Dampness Affecting Buildings
Dampness in buildings can show itself in various ways, the three main types of damp problems commonly found whilst carrying out damp surveys in houses are; rising damp, penetrating damp and condensation, I have described below the typical symptoms often found by each different damp problem;
Rising Damp
Rising damp is best described as slow upward movement of ground water in the base of walls and other ground-supported structures by capillary action. Although rising damp in excess of 1.5 metres has been recorded it is very rare, the height of rise is typically much lower and is rarely above 1.5 metres. Rising damp has been a widely observed phenomenon for over two hundred years. The legal requirement for damp proofing came in the form of the Public Health Act of 1875 which introduced the requirement for a damp-proof course in walls to prevent rising damp.
Typical Symptoms Of Rising Damp
Rising damp can be attributed to the failure or absence of an original damp proof course, materials used to control damp in older houses consisted of bitumen felt, slate and sometimes engineering bricks, these materials have in some cases broken down over the years and allowed damp to rise and show on internal wall finishes. However, breaching of an original damp proof course due to high external ground levels is more common, external ground levels for example block paving, tarmac, concrete yards etc should be a minimum of 150mm (6 inch) below the damp proof course. A damp survey will of course note any problems and potential future problems that you need to be aware of.
Penetrating Damp
Penetrating damp is a very common problem reported by homeowners, although when the homewoners contact us to look at their damp problem they are not aware of the problem being caused by penetrating damp. Causes of penetrating damp can be, defective guttering, porous brick work, poor pointing to brickwork, un-capped chimneys, soil from raised flower beds against walls and also sheds hard up against walls.
Severe Penetrating Damp From Defective Guttering
Homeowners first become aware of the problem when it’s starts to breakdown wall finishes internaly, in reality the problem has probably been their for sometime and eventually when the brick/stonework has become so saturated it starts to effect the internal plaster finish. Penetrating damp can easily be prevented by simple regular building maintenance, if left untreated penetrating damp can cause significant damage to a property and can lead to further attacks from the likes of Dry Rot which is a extremely destructive wood destroying fungus which is often referred to as the concer of a building.