Damp and condensation

Controlling condensation is important, especially in modern, well insulated homes. Condensation is caused by moisture in the air. It is not usually caused by a building fault. At some time, condensation will occur in every home.

Why have I got condensation in my new home?

It is quite usual for there to be a problem with condensation in new build homes as they are built so efficiently that there is no way for moisture or condensation to escape. Also, in new homes, extra moisture can be produced by building materials which can take a few months to dry out.

What is condensation?

Condensation is caused by everyday activities such as cooking, washing and bathing. This can lead to problems with mould which looks unpleasant and can cause health problems.

There are three main causes of condensation:

  • Too much moisture in your home 
  • Too little ventilation
  • Cool temperatures

How can I reduce condensation?

Although you are unlikely to completely stop condensation, you can reduce it by following these tips:

  1. Keep your home well ventilated 

    Open one or two small windows slightly for 30 minutes each day. Remember to close them when you go out. 

    Leave trickle vents (slotted vents in the window frames) open when rooms are occupied – even in the winter when your heating is on. These vents provide constant ventilation which removes water vapour. 

    Avoid putting too much in cupboards and wardrobes, as this stops air from circulating and where possible, do not place wardrobes against outside walls.

  2. Keep your home well heated 

    Heating your home efficiently helps reduce condensation and could save money on your heating bills. It’s important to keep your home above 18°C (63°F). 

    Use room thermostats and radiator controls to maintain an even temperature in your home. Heat rooms at a low temperature, even if they are unused.

  3. Reduce moisture in your home 

    Wipe excess condensation off windows and surfaces with a towel each morning. 

    Dry washing outdoors on a line, or put it in a bathroom with the door closed and the window open. 

    Cover pans when cooking and do not leave kettles boiling. 

    Open windows or leave an extractor fan on for at least 20 minutes when you have been cooking, or had a bath or shower, and keep the door closed. When running a bath, add cold water before hot as this will greatly reduce steam which can lead to condensation.

What if I already have mould?

Mould, although unpleasant, can be treated very easily. You should remove mould as soon as it appears to prevent it spreading.

To kill and remove mould:

  • wipe down walls and window frames with a fungicidal wash, available from most supermarkets and hardware stores.
  • do not use a vacuum cleaner or brush to remove mould as this can release spores, which may make the problem worse.
  • use fungicidal resistant paint and wallpaper paste for any redecoration after treatment

What if it isn’t condensation?

Condensation isn't the only cause of damp. It can also come from:

  • leaking pipes and waste overflows
  • rain seeping through the roof where tiles or slates are missing
  • overflow from blocked gutters penetrating around window frames or leaking through cracked pipes
  • rising damp due to a defective damp-course or because there is no damp-course

These causes of damp often leave 'tide marks'. If this does occur you can report it using the Repairs section of Your Waterloo, or with our online form.

You can find out about effective ways to heat and insulate your home from the Energy Savings Trust on 0845 727 7200 or at www.est.org.uk.