Dealing with Damp and Condensation

What is the cause of condensation?

Condensation is caused when moisture held in warm air meets a cold surface like a window or a wall and condenses into water droplets. If this happens on a regular basis, mould will start to grow. This usually appears on cold outside walls and surfaces, and in places where the air does not circulate well, in cupboards or corners of rooms. The moisture created can also damage clothing, furniture or fixtures and can leave a musty smell. During the winter and on colder mornings, you are likely to get a bead of condensation on your windows. All houses are affected by condensation at some time. It usually occurs when a lot of moisture and steam are produced.

For example:

  • When cooking
  • Having a bath or shower
  • Drying washing within the home or using a tumble dryer that is not properly vented to the outside
  • When the outside temperature drops causing the windows to mist up regardless whether it is raining or not
  • The use of portable paraffin/gas heaters.

What can I do to prevent condensation?

These simple steps will help to prevent condensation occurring in your home:

  • Put lids on sauce pans when cooking
  • Try not to dry clothes within the home but if you have to, confine to one room and have the window open and the door shut to prevent moist air travelling throughout the property
  • If using a tumble dryer make sure it is properly vented to the outside
  • Put a small amount of cold water into the bath before running the hot water
  • Do not run your shower longer than needed
  • After bathing or showering dry down or squeegee wet wall or tiles to stop moisture being absorbed into the air, open the window and leave the door closed on exit
  • Close doors on kitchen and bathrooms and always use extractor fans
  • Wipe condensation from windows, particularly on cold days with a dry cloth
  • Ventilate your home as much as possible by opening windows and trickle vents
  • Keep furniture such as beds, wardrobes etc, clear of the room’s external walls to let the air circulate
  • Make sure you are heating all rooms.

Given the right conditions condensation will form on any surface but is often more visible on windows.


If you start to notice mould spores starting to grow on windows, ceilings or walls, it is important to deal with it promptly. Wash the area with a suitable cleaning product, and then wash the area with fungicide mould inhibitor (this can be found at any DIY shop). Wallpaper may need to be stripped from the area before treatment. Carpets and soft furnishings should be shampooed, not brushed, as brushing will release mould spores into the air, which can sometimes be harmful to adults, children and pets.

If possible, leave heating set at a low setting when not in the property and select boost on your return to reduce the risk of low internal temperature and creation of condensation.

By keeping your house warm this will cut down on condensation as moisture does not condense in warm air.


Houses do not create moisture, human activity does.