Keep your home free from damp and mould

Damp and Mould cover Is your home damp?

Damp can cause mould on walls and furniture and make timber window frames rot. Damp encourages the growth of mould and mites and can increase the risk of respiratory illness.


What is condensation?

Some damp is caused by condensation which is created by non-visible moisture in the air. When air gets colder, it cannot hold all the moisture and tiny drops of water appear. You may notice it when you see your breath on a cold day, or when the mirror mists over when you have a bath.

Condensation occurs mainly during cold conditions, whether it is raining or dry. It does not leave a ‘tidemark’. It appears in places where there is little movement of air. Look for it in corners, on or near windows, in or behind wardrobes and cupboards. It often forms on north-facing walls.


Other causes of damp

Condensation is not the only cause of damp. Damp can also come from:

  • Leaking pipes, wastes or overflows.
  • Rain seeping through the roof where a tile or slate is missing, spilling from a blocked gutter, penetrating around window frames, or leaking through a cracked pipe.
  • Rising damp due to a lack of, or a defective damp-course.

These causes of damp often leave a ‘tidemark’. If your home is damp for any of these reasons it may take weeks of heating and ventilating to dry out. Hiring a dehumidifier will help. If you do not think the damp comes from any of these causes, it is probably condensation.


First steps against mould

First treat the mould already in your home. Then deal with the basic problem of condensation and mould should not reappear.

  • To kill and remove mould, wipe down walls and window frames with a fungicidal wash which carries a Health and Safety Executive ‘approval number’
  • Follow the manufacturer’s instructions precisely. Dry-clean mildewed clothes, and shampoo carpets. Disturbing mould by brushing or vacuum cleaning can increase the risk of respiratory problems.
  • After treatment, redecorate using a good quality fungicidal paint to help prevent mould recurring. Note that this paint is not effective if overlaid with ordinary paints or wallpaper.

The only lasting way of avoiding severe mould is to eliminate dampness.


3 steps to help reduce condensation in your home

1. Produce less moisture

Some ordinary daily activities produce a lot of moisture very quickly.

  • Cover pans and do not leave kettles boiling
  • Avoid using paraffin and portable flueless bottled gas heaters as these heaters put a lot of moisture into the air.
  • Dry washing outdoors, or in the bathroom with the door closed , the window open or fan on.
  • Vent any tumble dryer on the outside, unless it is the self-condensing type. DIY kits are available for this.


2. Ventilate to remove moisture

It is possible to ventilate your home without causing draughts

  • Keep a small window ajar or a trickle ventilator open when someone is in the room.
  • Ventilate kitchens and bathrooms when in use by opening the windows wider. Better still, use a humidistat-controlled electric fan (these come on automatically when the air becomes humid and are cheap to run).
  • Close the kitchen and bathroom doors when these rooms are in use, even if your kitchen or bathroom has an extractor fan. Doing this will help stop the moisture reaching other rooms, especially bedrooms, which are often colder and more likely to get condensation.
  • Allow space for the air to circulate in and around your furniture. Open doors to ventilate cupboards and wardrobes. Leave space between the backs of wardrobes and the wall. Where possible, position wardrobes and furniture against internal walls.
  • When you have a curtain or blind drawn, it makes the surface of the window cooler and increases condensation, especially with single glazed windows. If you replace your windows at any time, make sure they are double glazed and fitted with trickle ventilators.


3. Insulate, draught-proof and heat your home

  • Insulate your loft. Remember to draughtproof the loft hatch but do not block the opening under the eaves.
  • Consider cavity wall insulation. Before deciding though, you should talk to your local building inspector as building regulations approval is required.
  • Consider secondary and double glazing of windows to reduce heat loss and draughts but you must ensure that there is some ventilation.
  • In cold weather keep low background heating on all day, even when there is no one at home.