Condensation

Find out what condensation is and how you can reduce it in your home.

What is condensation?

Condensation starts as moisture in the air. It’s usually produced by cooking, showering/bathing or by drying clothes indoors or on radiators. If left unchecked, it can become a serious problem.

All homes suffer from condensation from time to time, but severe condensation is common in cold weather and in older properties.

Condensation tends to affect walls behind large pieces of furniture, the corners of rooms where there is less airflow, colder outside walls, windows, kitchens, and bathrooms.

Signs of condensation include water and mould collecting on ceilings, walls and windows.

How condensation forms

Condensation happens when moisture in the warm air touchers a cold surface. The air in our homes always has moisture in it, even though you can’t see it. The warmer the air, the more moisture there is. When the warm moist air hits a cool surface (such as a wall, mirror or window) the moisture condenses (becomes liquid).

Why is condensation a problem?

Condensation  is the most common cause of damp and mould in buildings. It can lead to running water on windows and walls which can cause damp.

Damp in housing is unhealthy, smelly and encourages the growth of mould and mites. This can increase the risk of illness. Mould can leave stains on walls and furnishings and cause wooden windows to rot.

What can I do to reduce condensation?

There are three ways to reduce condensation.

Produce less moisture

  • Cover pans when cooking and turning kettles off as soon as they boil
  • Open kitchen and bathroom windows when cooking or washing so that steam can escape, or use an extractor fan if you have one fitted
  • Dry washing outdoors wherever possible, otherwise use well-ventilated rooms
  • Running the vent from your tumble dryer to the outside, unless it is the self-condensing type
  • Avoiding the use of bottled gas heaters as they produce a lot of moisture
  • Fitting lids to fish tanks as evaporation of water from these can be high

Increase ventilation

  • Keep a small window open for a short time each day to allow for a change of air
  • Close kitchen and bathroom doors when in use and opening a window to stop steam going into other rooms
  • Install a small extractor fan in the kitchen or bathroom to remove moisture – these are the two rooms most responsible for condensation
  • Making sure air bricks in walls are not sealed

Keep your home warm

  • Heat your home at a low constant temperature during the cold weather rather than heating one room to a high temperature. Remember that condensation affects rooms you are not heating
  • Keep radiators clear to allow warm air to circulate
  • Reducing draughts from windows and doors as much as you can

Treating mould

Prevention is better than cure so wipe down surfaces where moisture settles. This will prevent mould forming and spreading to your personal belongings.

Remove any mould by wiping it off with an antifungal solution (not washing-up liquid or water) and applying a sealant solution to the wall or surface.

You can buy antifungal solutions and sealants from hardware or DIY stores. You should always read and follow the instructions carefully.

Do not disturb mould by brushing or vacuuming it. This can increase the risk of illness.

Other damp problems

Some damp may cause a tidemark. Typical causes of this include leaking pipes or waste pipes, leaking roofs, blocked gutters, leaking window frames or rising damp.

If this happens in your home, please report it to us. We can then tackle the issue and make sure your home is not damaged.

More information

For more details  information on how you can reduce condensation in your home, download our leaflet

Condensation leaflet (809kb)