Weather and Damp Protection part 1
Published in the Cyprus living Magazine Dec 2007
With this article I would like to look into the effects of rain and sunshine, something that we get in abundance here in Cyprus, and how this will affect your property.
A question of structure
In the United Kingdom our homes are built to strict guidelines they are usually brick construction with cavity walls. The correct damp proof courses are built into the walls and floors ensuring their effectiveness from rising damp and driving rain. Usually a good guttering system is also installed.
In Cyprus this may not be the case. The buildings usually have no wall cavities and generally no damp proof course. Floor membranes can be missing, damaged or insufficient this means that many of our properties are exposed to damp and this will bring problems.
The most common type of damp is rising damp. Moisture from the ground rises, by capillary action, up the walls. The moisture often carries salts which are deposited on the face of the wall when the moisture evaporates. Internal decorations are stained and damaged, plaster can “debond” and become loose. Rising damp only extends up to 1 meter above ground level; the capillary forces cannot lift the moisture any higher. Normally walls are protected against rising damp by a damp proof course built into the wall. Very old properties did not have damp proof courses, and old properties may have damp proof courses which have become ineffective. Sometimes the outside ground levels are raised above the damp proof course, this is called 'bridging'.
The solution to rising damp is usually to inject a chemical damp proof course, and to re-plaster the internal walls with a waterproof layer up to 1.2 meters high. This work usually comes with a 10, 20 or even 30 year guarantee. However this does not work in Cyprus that well because of the way the buildings are made, chemical injection relies on the chemical spreading its way through a mortar course with conventional brick work.
This is caused by moisture which penetrates through the roof or walls. Roof problems are usually evident. Damp penetrating through walls, which includes flashings at roof and chimney abutments, is usually quite evident, but it is usually very difficult to pinpoint and cure the precise cause of the problem and very often there is no quick or easy solution. Penetrating damp can sometimes be caused by gutter or roof problems which allow rainwater to spill onto and saturate areas of wall.
This is the third type of damp. This is usually caused by the lifestyle of the occupants, rather than a defect with the property. Lack of ventilation and a tendency to use the radiators for drying clothes are common causes.