Condensation, damp and mould

Different types of damp can affect a property but it is often caused by condensation, which can be avoided if the right steps are taken.


Condensation is usually more of a problem in winter, when windows are closed and it is colder. 

Forming when warm moist air comes into contact with cold surfaces such as a window or external wall, it can develop into black mould if it is left.

Ventilation and air circulation around your home is very important as moisture-filled air can escape to the outside and be replaced with drier air from outside.

Over time our homes have become more efficiently sealed and most reports we get about mould are found to be caused by a lack of ventilation causing condensation.

Our everyday activities add extra moisture to the air inside our homes. Even our breathing adds some moisture. One person asleep adds a half pint of water to the air overnight and twice that when active during the day. 

Below is an idea of how much extra water this could be in a day:

Two people at home for 16 hours
A bath or shower
Drying clothes indoors
Cooking and use of a kettle
Washing dishes

Tackling condensation

Reduce moisture
  • Put lids on saucepans
  • Dry clothes outside or hang them in the bathroom with the door closed and a window slightly open or extractor fan on. Don’t be tempted to put them on radiators
  • Make sure tumble dryers are vented to the outside or are a condensing type
  • Take a bath or shower with the bathroom door shut
  • Wipe any moisture off of windows and off of mirrors and tiles in the bathroom 
Ventilate your home
  • In bathrooms and kitchens use the extractor fan if you have one, or open a small window for about 20 minutes after use
  • Keep window trickle vents open or open windows for at least 10 minutes during every day
  • Keep furniture, including beds, away from external walls, try to leave a gap between the wall and furniture to allow air to circulate
  • Don’t overfill wardrobes and cupboards as this can restrict air circulation
  • Don’t block permanent ventilators or airbricks and don’t draught proof bathroom or kitchen windows
  • Be careful not to over-ventilate your home when it is cold, it causes the temperature to drop and makes condensation more likely
Reduce cold surfaces

Keeping your home warm:

  • means there are fewer cold surfaces for condensation to form on.
  • helps to control condensation as the warm air holds more moisture and is less likely to deposit droplets of condensation

Heating one room and leaving other rooms cold makes condensation worse in the unheated rooms. It is better to have a medium-to-low level of heat throughout the whole of your home.

We realise that for many people money is tight, but keeping the heating on low all day in cold weather will help to control condensation.

Treat mould
  • Remove mould from walls using a special fungicidal wash or specific mould remover making sure you follow the manufacturer’s instructions. Throw away any cloths that you use
  • These can be found at supermarkets, hardware shops or DIY stores. Do NOT use bleach
  • Dry-clean mildewed clothes and shampoo carpets
  • Do not try to remove mould by using a brush or vacuum cleaner, you’ll only spread it around
  • After treatment, redecorate using good-quality fungicidal paint and fungicidal resistant wall paper paste to help prevent mould recurring, but unless you take steps to reduce condensation it will eventually grow back

This Skill Builder video gives a comprehensive overview of black mould and explains how it can be avoided.

Next steps

If you are a council housing tenant and have tried all of the above and still have condensation, damp and mould in your home, contact the Crawley Repairs Team. Complete our online form or call 01293 438111 or email

Report condensation, damp and mould in your home