Condensation is produced when warm air containing water vapour comes into contact with a cold surface such as a window or a wall. It usually happens during normal activities such as having a shower, washing and drying clothes or boiling a kettle.
If condensation forms in a place where there is little or no ventilation, it can form a black mouldy looking growth. The sight of this can be worrying, but there are simple steps you can take to prevent and treat mouldy patches. It’s also important to remember that most cases do not occur as a result of any structural damage to your home.
Produce less moisture
- Use lids on saucepans to reduce steam.
- Avoid using radiators to dry clothes.
- Vent tumble driers to an open window or outside.
Stop moisture spreading
- Open windows or use extractor fan during cooking or washing.
- Keep windows open for 20 minutes after activity.
- Wipe away condensation when it appears.
- Open your window vents when inside a room.
- Leave gaps between furniture and walls.
- Avoid overfilling wardrobes and drawers.
Provide even heating
- Keep your home warm to prevent condensation forming.
- Leave your heating on lower for longer.
- Keep all rooms heated, including ones you don’t use.
Treating mould caused by condensation
What to do if you notice mould in your home
- Treat it straight away to prevent it spreading.
- Sterilise the affected area with a fungicidal wash and keep an eye on it – if it comes back, treat it again.
- If it clears up, paint the affected area with some fungicidal paint or, if using wallpaper, use paste with fungicidal properties.
- Dry clean carpets or clothes with mould growing on them, vacuuming or brushing the mould can be hazardous to your health.
- Prevent mould from forming by wiping up any condensation you see in your home.