subject: The impact of damp and mould on a property [print this page] The impact of damp and mould on a property
There are various forms of damp and mould that can get a real hold on a property and the situation can be particularly acute in empty office or commercial premises. These buildings may remain vacant for many months and where a property has a large square footage, the early signs of damp problems can remain undetected.
However, no-one will mistake the subsequent signs of damp: a musty smell, black or white mould appearing on surfaces, a cold feeling on the walls, brown stains or a tide mark around the wall. At this stage, it is most likely that some sort of structural repairs (such as fixing leaking pipes or the damp proof course) need to take place to ensure that the damp does not return. In the short term, it is wise to use a dehumidifier.
A dehumidifier will dry the air in the room which in turn will allow the wall or floor to release the moisture that it is holding on to. Until the route cause of the problem is fixed, the cycle will continue with the building sucking in more moisture and the dehumidifier clearing it out. However, using a dehumidifier will help to control the problem until a suitable plumber or builder has been found.
So what produces this damp?
Damp in buildings can be produced by a number of different things: a small leak in a roof in to a heated room can be the culprit, as can poor heating, boiling the kettle for a cup of tea or various manufacturing processes. On a hot summer's day it may seem like a viable option to just open the windows but in winter you may lose all the heat, create draughts and could let more moisture in if it is raining.
It is a simple fact of physics that when water vapour passes over a cold surface it condenses and returns to a liquid state. Within the air there are always mould spores floating around but they cannot turn into mould unless they land in moisture and this is when properties fall prey to a mould infestation.
Dehumidifiers work by mirroring the above mould-producing process but inside the machine itself rather than on walls and surfaces. The warm, moist air enters the dehumidifier and is cooled, at once turning to a liquid. This water is dripped in to a container then reheated back to room temperature and blown out of the back of the dehumidifier in a controlled process. A dehumidifier will not get rid of existing mould but it will prevent it from getting any worse and once the mould has been cleaned away, it will stop if from coming back.
Powerful refrigerant dehumidifierscan handle up to 890 litres dehumidification capacity a day, delivering high levels of drying power. In a British climate this typically provides keep-dry areas up 13,600m3 and dry out areas up to 6,400m3: dry out is required either after flooding or during building construction to accelerate the rate of drying wet materials. In addition to a dehumidifier, some situations will also require an air mover too. Air movers dry the superficial traces of water to ensure better performance out of the dehumidifier
To correctly decide upon the most efficient way of drying an area, many factors may need to be considered: temperature, materials, relative humidity and drying time. This type of calculation is best left to the experts who armed with a hygrometer and psychrometric chart will be able to give advice and select the most appropriate dehumidifier.
