This news article explains how condensation forms and how you can keep it to a minimum, thus reducing the risk of dampness and mould growth.
Damp can cause mould on walls and furniture and make timber rot. Damp in housing encourages the growth of mould and mites. Damp is more often than not caused by condensation forming on cold surfaces. It can also be caused by rising damp or weather penetration.
What is Condensation?
Condensation is dampness occurring when air laden with water vapour cools on contact with a cold surface, you notice it when you see your breath on cold days or in the bathroom on mirrors or tiled surfaces. Condensation frequently occurs during cold weather and appears on cold surfaces and in areas of the dwelling where there is little movement of air.
Condensation is frequently found on or near windows, cold wall surfaces and in or behind cupboards or wardrobes. Also it often forms on north facing walls.
Is it Damp or Condensation?
Does it leave a tidemark? - If so, it is not condensation, the source of a leak or dampness needs to be inspected, this could be from rain seeping through windows or rising dampness due to a defective or missing damp proof course.
HOW TO MINIMISE CONDENSATION
Produce less moisture
Ordinary daily activities produce a lot of moisture, often very quickly.
Cover boiling pans and turn kettles off after use.
Avoid paraffin and portable gas heaters as these add moisture to the air in the dwelling.
Dry washing outdoors or in the bathroom with the door closed, window open or fan turned on.
Vent tumble dryers using correct vent kits. Self-condensing types reduce the amount of moisture, but they are not as good as a vented type.
Avoid drying clothes on radiators/heaters.
Ventilate to Remove Moisture
Keep a small window or trickle vent open when the room is in use.
In particular, ventilate kitchens and bathrooms when you are using them.
Prevent the damp air spreading by keeping kitchen and bathroom doors closed when the room is in use.
Open curtains for at least 4 or 5 hours each day, this allows moisture to get through any window vents.
Do not completely draught-proof windows, especially in the kitchen or bathroom as this assists airflow.
Do not blank off vents.
Ventilate cupboards and wardrobes, do not put too many things in them so preventing circulation. Where possible put them on internal walls.
Keep Your Home Warm
Heat your home at low levels for a long time rather than high levels for short periods, this will ensure that fewer cold surfaces form in the home.
Heat the home even when there is no one there. Keep background heating on all the time during winter months.
Heat using a dry source, for example gas central heating or electric storage heaters or a fitted gas fire. Do not use paraffin or portable gas heaters.
Insulation and sensible draught proofing will help keep your home warm and will also cut fuel bills.
Dealing with Mould Growth
If mould starts to grow on walls, clean them with a suitable cleaning agent.
Try to ensure that condensation does not occur on a regular basis.