Condensation & Mould


Some helpful information…

If you would like to view the information contained in this guide in another language then please visit:
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For further information about condensation and mould in your home visit:
If you have any concerns about mould in your home then contact:
Liverpool City Council
0800 012 1754
or email


The four main factors that cause condensation:

  1. Too much moisture being produced in your home
  2. Not enough ventilation
  3. Cold surfaces
  4. Temperature of your home

What is condensation?

Condensation occurs when warm, moist air meets a cold surface.
There is always some moisture in the air, even if it cannot be seen. When air cools it cannot hold all the moisture and tiny drops of water appear. If moist air cannot escape through an open window or air vent, it will move around your home until it finds a cold spot such as a window, mirror or tiled wall, where it will become condensation. This may lead to mould growth.
Condensation occurs in cold weather, even if the weather is dry. If there is a ‘tidemark’, this may be due to condensation or might have another cause such as water leaking into your home from a plumbing fault, loose roof tiles or even rising damp.
Problems that can be caused by excessive condensation.
Dampness caused by excessive condensation can lead to mould growth on walls and furniture, mildew on clothes and other fabrics and the rotting of wooden window frames. Damp humid conditions also provide an environment in which house dust mites can easily multiply. The presence of mould and dust mites can make existing respiratory conditions, such as asthma and bronchitis worse.



Reduce the potential for condensation by producing less moisture


Steps you can take to reduce condensation in your home:

  • Try not to dry clothes inside or, if you must dry them inside, do not be tempted to put them on a radiator or in front of a radiant heater.


  • Always cook with pan lids on, turn the heat down once the water has boiled and only use the appropriate amount of water for cooking vegetables. 


  • When filling a bath, run the cold water first, it will reduce steam by 90%. 


  • Keep the kitchen and bathroom doors closed when cooking or bathing to stop moisture moving around your home. 


  • Avoid using your gas cooker to heat your kitchen since it produces moisture when burning gas and it is an expensive way to heat a room.


  • When using a tumble drier, make sure it is vented to the outside or that it is a condensing type. 


  • Avoid using mobile bottled gas heaters, as they can produce about 8 pints of water per average gas cylinder, and can be dangerous if there is not enough ventilation in the room.



Ventilating your home


Proper ventilation is a key step in reducing condensation in your home:

  • Ventilation can help to reduce condensation by removing moist air from your home and replacing it with drier air from outside.


  • Reduce condensation that has built up overnight by “cross ventilating” your home. Open a small window downstairs and a small window upstairs for about 30 minutes. Opening up the room doors will allow drier air to circulate throughout your home. NOTE: Please ensure that opening windows will not create a security problem and close the windows before leaving the house.


  • Ventilate the kitchen when cooking, washing up or washing by hand by opening a window – even opening a window slightly can be effective. Use a cooker extractor hood or extractor fan, they are cheap to run and very effective.


  • Ventilate your bedroom by leaving a window slightly open at night, or open the trickle ventilators if you have them.


  • Keep kitchen and bathroom doors closed to prevent moisture getting into the rest of the house.


  • Do not block air vents.


  • Reduce the risk of mildew on clothes by allowing air to circulate. Never over fill wardrobes and cupboards as it restricts air circulation.


  • Place furniture on blocks to allow air to circulate underneath.


  • Keep a small gap between large pieces of furniture and the walls.


  • Do not turn off fan isolator switches.



Why is too much moisture produced in your home?


Everyday activities add extra moisture to the air inside your home. Even one person asleep overnight will add half a pint of water to the air. To help illustrate how easy it is to add moisture to the air in your home it is useful to know that:

2 people at home can produce 

3 Pints 


A bath or shower

2 Pints


Cooking and use of a kettle

6 Pints


Washing dishes

2 Pints


Bottled gas heater (8 hours)

4 Pints


Drying clothes indoors

9 Pints


Total moisture added in 1 day:

26 Pints or 14.8 Litres



Cold surfaces

Condensation forms more easily on cold surfaces in your home.
In many cases, surfaces can be made warmer by improving the insulation and draught-proofing. This will also help keep your whole house warmer and cut fuel bills. When the whole house is warmer, condensation becomes less likely. Loft and wall insulation are the most effective forms of insulation.

If you install draught proofing then do not:

  • Draught proof rooms with a condensation problem, or where there is a cooker or heater that uses gas or solid fuel.


  • Block permanent ventilators or airbricks installed for heating or heating appliances.


  • Draught proof bathroom or kitchen windows.

If you believe that your home could benefit from improving the loft or wall insulation then contact your landlord.


Temperature of your home

It is better to have a medium to low level of heat throughout your home.

Warm air holds more moisture than cooler air that is more likely to deposit droplets of condensation around your home. Heating one room too much and leaving other rooms cold makes condensation worse in the unheated rooms. Therefore it is better to have a medium to low level of heat throughout your home. Keeping the heating on low all day in cold weather will help control condensation however, check on your meters to be aware of how much it is costing you to do this. Use the controls on radiators to get a little heat into every room.



Steps against condensation…

It is important to take proper steps to deal with condensation, here are some simple things you should do straight away:


  • Dry windows and window sills every morning
  • Dry surfaces in the kitchen or bathroom that have become wet
  • Wring out the cloth rather than drying it on a radiator
  • Improve ventilation in your home
  • Maintain an adequate temperature


Steps against mould growth…

Step 1

First treat the mould already in your home, and then deal with the basic problem of condensation to stop mould reappearing.


Step 2

To kill and remove mould, wipe down or spray walls and window frames with a fungicidal wash e.g. mould and mildew cleaner.


Step 3

Dry clean mildewed clothes and shampoo carpets.


Step 4

Do not try to remove mould by using a brush or vacuum cleaner.


Step 5

After treatment, redecorate using good quality fungicidal paint or a fungicidal resistant wallpaper paste to help prevent mould recurring.





Useful contact telephone numbers


Gas Leaks – National Grid

0800 111 999 

Power Cuts

0845 272 7999 

Energy Gas and Electricity Consumer Advice

0845 906 0708 

Winter Fuel Payments

0845 915 1515 

Age UK

0800 009 966 

Additional Pension Enquiries

0800 99 1234 

Disabled Living Foundation

0845 130 9177 

Enquiry Line for People with Disabilities, and their Carers

0800 882 200 

For Tenants with existing E.A.G.A. Heating Systems problems 

0800 316 6011



Further Information
To receive a Liverpool City Council Energy Advice Pack regarding:

• Energy saving tips

• Information on energy efficiency grants

Call Freephone: 0800 012 1754
or email:


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