Keeping your home free from damp and mould
The number one cause of mould in homes in the UK today is under-heating.
You will get less mould if you keep your home warm, ventilate properly and minimise the amount of moisture you release into the air.
This guide aims to help you understand what condensation and mould are, and how their growth can be minimised.
An example of condensation on a window
What is Mould?
Mould grows and multiplies in moist areas, slowly at first then quicker and quicker. It is normal to have some mould growth in winter but, you need to stay on top of it to prevent it from getting more serious.
What is Condensation?
Condensation comes from cooking, cleaning, bathing, even breathing. Condensation will form on the coldest surfaces in the room first, these cold areas are usually around windows, the corners, and external walls.
Condensation occurs mainly during cold weather, whether it is raining or dry. Condensation is not necessarily a problem, as long as the surface has time to dry out every day.
What is Damp?
Damp is a place where moisture collects but does not have a chance to fully dry out. Damp is very common in the UK and is nearly always due to condensation. Damp usually builds up in areas where there is not much air movement.
An example of damp and mould growth from condensation around a window
So, what can you do?
1. Minimise the amount of moisture in your home
- Drying clothes in one of the following ways:
- Outside if possible.
- In a room with a window open or extractor fan running and the doors closed.
- In a tumble dryer venting outside or using a special condenser.
- Never put wet clothes on a radiator - they fill the room with moisture in seconds.
- Keep lids on saucepans while cooking.
- Don't use paraffin or other bottled gas heaters - they are dangerous and release huge amounts of water vapour.
- Always run the extractor fan or open a window when cooking or showering. Keep the door closed to stop the moist air from going into other rooms.
- Put cold water in the bath before adding hot.
- If you have trickle vents* on your windows, keep them open.
2. Improve air movement around areas prone to mould
- Pull all furniture, including beds, away from external walls, especially from any corners.
- Try to leave a gap behind curtains and the wall during the day.
- Keep air bricks, extractor fans open and clear.
- Don't draught-proof kitchens and bathroom windows, or rooms that are prone to damp.
- Don't overfill cupboards and shelves where mould tends to form. Where possible, position wardrobes and furniture against internal walls.
*A trickle vent above a window - these should be left open at all times to allow air flow
3. Minimise the number of cold surfaces
- Heat your home to a reasonable level of warmth to avoid damp building up in winter. If you don’t want to heat your entire home, keep the doors shut on unheated rooms.
- The World Health Organisation guidelines suggest 21 degrees in a living room and 18 degrees in the bedrooms, falling lower at night and when you are out. You don’t need to keep your home at these temperatures all the time, but you should aim to bring it up to these temperatures at least some of the day.
4. Wipe down small patches of mould before they spread
- Wipe down condensation from windows and other areas in the morning, with a dry cloth and open a window for a while. Wring the cloth in the sink rather than drying it on a radiator.
- When you spot black dots of mould, wipe it with a mild bleach solution or anti-fungal spray. These are readily available from supermarkets. You might need to do this at least twice a month in winter.
5. Treat bad outbreaks of mould
- Wash or dry-clean mildewed clothes and shampoo your carpets.
- After treatment and once dry, redecorate using good quality fungicidal paint to help prevent mould recurring. This paint is not effective if covered with ordinary paints or wallpaper.
It is the resident’s responsibility to deal with damp caused by condensation. In most cases black mould is related to condensation - this leaflet provides guidance for how to deal with it.
Other kinds of Damp
Penetrating Damp from roof, window and plumbing leaks can happen. This kind of damp is usually focused in one place and once the leak is fixed, will dry with time. These faults rarely leave black mould. These problems need to be reported so that we can arrange for them to be fixed for you.
Rising Damp is caused by water soaking up the wall, no more than 1m. In fact, this sort of damp is extremely rare and almost never causes black mould. Rising damp can only be cured through major works.
A damp-proof course (DPC) is a barrier in a masonry wall designed to resist moisture rising through the structure. Be careful not to allow the damp proof course to become bridged by the build-up of plants and soil, or by building a patio.
Key things to remember:
- Open windows and use extractors when cooking, bathing or showering
- Dry clothes in ventilated rooms or outside, they will dry twice as fast.
Never put them on the radiator
- Use your heating effectively, the ideal temperature is 21 degrees (recommended by World Health Organisation)
- Wipe down patches of mould as soon as you find them, never wait until they get worse.
Please remember that cleaning and redecorating following mould is your responsibility. This guide gives you the information you need to deal with the problem and help prevent it from coming back. Regular cleaning of affected walls is necessary to keep mould away.