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Condensation and Mould

There is always some moisture in the air, even if you cannot see it. If air gets cold, it cannot hold all the moisture produced by everyday activities and some of this moisture appears as tiny droplets of water, most noticeable on windows on a cold morning. This is condensation.

Dampness and mould growth on the walls and ceilings is a common problem, particularly in the winter months. Look out for shiny patches on paintwork or discoloured paper initially. This will be particularly prevalent in the corners, around edges of the ceiling, to external walls and around window frames. Condensation forms on cold surfaces, particularly where there is little movement of air.

If untreated mould may start to grow in these spots. This is characterised by black spots on the walls and ceiling, increasing in size. Also characteristic of condensation problems is mildew (more furry and greenish grey) on furniture, clothing and furnishings.

Damp and humid conditions are also a breeding ground for dust mites which along with mould spores can exacerbate existing conditions such as Asthma.

Tackling condensation and mould:

  • Reduce the amount of moisture produced in your home. Avoid drying clothes indoors. If you must, keep it to a well ventilated (window open) room with the door closed
  • If you use a tumble dryer make sure it is vented to the outside
  • Keep doors closed when bathing/ showering or cooking and ventilate the rooms (mechanically or naturally)
  • Try to avoid the use of bottled gas heaters
  • Help reduce condensation that has built up overnight by cross ventilating your home during the day. Open a small window downstairs and a small window on the opposite side of the house upstairs and open the doors to allow fresh air to circulate through the house
  • Keep trickle vents open in bedrooms during the night
  • Help air to circulate by keeping a small gap between larger items of furniture (wardrobes, cupboards, sofas) and the walls or floors
  • Ensure the surfaces of your home are as insulated as possible. Install loft insulation, double glazing, wall and floor insulation. Condensation forms more easily on cold surfaces. For help with installation costs please visit our energy efficiency and financial assistance pages
  • Increase the temperature in your home. Warm air holds more moisture than cold air and is less likely to deposit the moisture as condensation. A steady temperature (rather than fluctuations) also helps combat condensation
  • To kill and remove mould, wipe down or spray walls and window frames with a fungicidal wash that carries a Health and Safety Executive (HSE) 'approval number', and ensure that you follow the instructions for its safe use. These fungicidal washes are often available at local supermarkets. Dryclean mildewed clothes, and shampoo carpets. Do not try to remove mould by using a brush or vacuum cleaner. Mould will reappear unless the underlying condensation issues are tackled

Remember, if the damp patches have a 'tide mark' or salt deposits or correspond with an external defect, or are in areas not associated with cold spots (such as internal walls) then the dampness is likely to be penetrating or rising damp, caused by a leaking pipe, loose guttering or some other defect. This would usually be the landlords responsibility and you should report the defect to them as soon as it is noticed.