Mould will only grow when there is sufficient moisture available. Generally, Relative Humidity must remain above 50-55% for a prolonged period for mould to thrive. If there is mould growing in your property, then there is a moisture problem.
During Mould assessments, we look at the extent of the mould problem AND the underlying cause - moisture. Using dedicated testing equipment we determine whether the moisture is the result of excessive condensation, leaks or rising damp.
Our recommendations for mould remediation always include methods to reduce or eliminate the moisture problem. Rising damp actually describes the movement of moisture upward through permeable building materials by capillary action.
It becomes a problem if the moisture penetrates vulnerable materials or finishes, particularly in the occupied parts of a building.
This moisture will dissolve soluble salts from the building materials such as calcium sulphate, and may also carry soluble salts from its source.
If the moisture evaporates through a permeable surface, these salts will be left behind and form deposits on or within the evaporative surface.The moisture content of the structure may rise to a level at which decay organisms may grow, or the materials themselves may be adversely affected. For example, timber skirting boards or built?in bonding timbers along the base of walls may become infected and decayed by dry rot, wet rot, weevils or woodworm.
In very damp conditions, the inorganic materials themselves may lose their structural strength. This occurs most spectacularly with walls made of cob (earth) soaked with water. Damp conditions on the surface of walls, particularly in conjunction with condensation, allow the growth of moulds both on the surface and within porous or fibrous materials, such as wallpapers or carpets fitted against the base of the wall. Not only is this aesthetically unacceptable and damaging to finishes, but it can be a significant health hazard to occupants. Where evaporation takes place, the deposition of soluble salts on the surface or within the pores of materials can cause aesthetic and structural damage.