Condensation accounts for approximately 70% of reported damp problems in domestic dwellings. It can also be a contributory factor of infestation by wood boring insects and outbreaks of fungal decay.
Condensation can commonly be attributed to a lack of balance between heating and ventilation, resulting in a rise in relative humidity. Air can hold more water vapour when warm than when cold. When warm air is cooled, such as when the heating switched off at night, it will deposit the water that it can no longer retain, as condensation on a cold surface. A similar effect can be demonstrated by breathing onto a mirror or other cool surfaces.
An average family of 4 people can produce up to 16 pints of water vapour a day! This can come from drying wet clothes on radiators, using a tumble dryer, having showers & baths, cooking and of course breathing.
That’s a considerable volume of water vapour being stored by the warm air in a centrally heated, double glazed home. Cool air cannot hold the same amount of water as warm air and when the warm air comes into contact with a colder surface such as a wall or window, it will deposit moisture onto that surface.
This can lead to misted or streaming windows, walls that are wet to the touch, plus mould growth on walls, windows, furniture, furnishings and clothes.