Home Help: How to prevent condensation, damp and mould in your home this winter

As we enter the colder month, our homes are becoming more susceptible to condensation, damp and mould. However, steps can be taken to tackle condensation and prevent your home from becoming a hazard to you and your family. 

What is condensation?

There is always some moisture in the air, even if you cannot see it. If air gets cold, it cannot hold all the moisture produced by everyday activities and some of this moisture appears as tiny droplets of water, most noticeable on windows on a cold morning. This is condensation. It can also be seen on mirrors when you have a bath or shower, and on cold surfaces such as tiles or cold walls. 

Condensation occurs in cold weather, even when the weather is dry. It doesn’t always leave a ’tidemark’ round its edges on walls. If there is a ’tidemark’, this dampness might have another cause, such as water leaking into your home from a plumbing fault, loose roof tiles or rising damp. 

Look for condensation in your home. 

Condensation can appear on or near windows, in corners and, in or behind wardrobes and cupboards. Condensation forms on cold surfaces and places where there is little movement of air.  

What causes condensation?

• It’s caused when warm air hits a cold surface like a window or a wall. Mould can occur if a surface is left wet. 
• You’ll see a build-up in condensation when you cook, shower or dry clothes indoors. 

There are four main factors that cause condensation: 

1. too much moisture being produced in your home 
2. not enough ventilation 
3. cold surfaces 
4. the temperature of your home 

You need to look at all these factors to cure a condensation problem. 

What can I do to reduce condensation and mould?

The best thing to do is make sure air can circulate around your home, so open windows or use an extractor fan if you have one. Opening windows during/after a hot bath, shower or when you cook a meal is just one way you can combat condensation.  

Dry your windows and windowsills every morning, as well as surfaces in the kitchen or bathroom that have become wet. Wring out the cloth rather than drying it on a radiator. 

Top tips! 

Reduce the potential for condensation by producing less moisture 

As previously noted, condensation is a build-up of moisture which in the long run will turn into damp. To reduce the amount of moisture in your home, suggestions note –  

• Hang your washing outside to dry if at all possible or hang it in the bathroom with the door closed and a window slightly open or extractor fan on. Don’t be tempted to put it on radiators or in front of a radiant heater 
• Always cook with pan lids on and turn the heat down once the water has boiled. Only use the minimum amount of water for cooking vegetables. 
• When filling your bath, run the cold water first then add the hot – it will reduce the steam by 90% which leads to condensation. 

Improving ventilation in your home

Ventilation can help to reduce condensation by removing moist air from your home and replacing it with drier air from outside. If you have poor ventilation, condensation will sit on your surfaces and if not treated will likely turn in to damp. 

Help to reduce condensation that has built up overnight by ’cross-ventilating’ your home – opening to the first notch a small window downstairs and a small one upstairs. At the same time, open the interior room doors, this will allow drier air to circulate throughout your home. Cross-ventilation should be carried out for about 30 minutes each day. 

Note: Make sure that accessible windows will not cause a security problem – remember to close them when you go out. 

• Ventilate your kitchen when cooking, washing up or washing by hand. A window slightly open is as good as one open. If you have one, use your cooker extractor hood or extractor fan. 
• Ventilate your kitchen and bathroom for about 20 minutes after use by opening a small top window. Use an extractor fan if possible 
• Ventilate your bedroom by leaving a window slightly open at night or use trickle ventilators if fitted. (But again, remember your security). 
• Keep kitchen and bathroom doors closed to prevent moisture escaping into the rest of the house. 

Reducing cold surfaces in your home

Condensation forms more easily on cold surfaces in the home, for example walls and ceilings. In many cases, those surfaces can be made warmer by improving the insulation and draughtproofing. 

Insulation and draughtproofing will also help keep the whole house warmer and will cut your 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 any draughtproofing, observe the following guidance: 

• Do not draughtproof rooms with a condensation problem, or where there is a heater or cooker that burns gas or solid fuel. 
• Do not block permanent ventilators or airbricks installed for heating or heating appliances. 
• Do not draughtproof bathroom or kitchen windows. 

The temperature of your home

Warm air holds more moisture than cooler air which is more likely to deposit droplets of condensation round your home. Air is like a sponge; the warmer it is, the more moisture it will hold. Heating one room to a high level and leaving other rooms cold makes condensation worse in the unheated rooms. 

However, we understand with increasing heating costs that it is a very worrying time for some people, so the following tips may not be an option at this time, but if you can: 

• Try to have to have a medium-to-low level of heat throughout the house – keeping the heating on at low all day in cold weather will help to control condensation, but keep a check on your meters to check how much it is costing you. 
• If you don’t have heating in every room, you could keep the doors of unheated rooms open to allow some heat into them. 
• If you have a freezer, it is a good idea to put it in a space suffering from condensation, as the heat from the motor should help to keep condensation at bay. 

Be careful not to ‘over-ventilate’ your home when it is cold, as it will cause the temperature inside to drop and make condensation more likely. It will also increase your heating costs.  

First steps against mould growth

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

To kill and remove mould, wipe down or spray walls and window frames with a fungicidal wash that carries a Health and Safety Executive (HSE) ’approval number’ and ensure that you follow the instructions for its safe use. These fungicidal washes are often available at local supermarkets. Dry-clean mildewed clothes, and shampoo carpets. Do not try to remove mould by using a brush or vacuum cleaner. 

After treatment, redecorate using good-quality fungicidal paint and a fungicidal resistant wallpaper paste to help prevent mould recurring. The effect of fungicidal or anti-condensation paint is destroyed if covered with ordinary paint or wallpaper. 

But remember: the only lasting cure for severe mould is to get rid of the dampness. 

To find out more about condensation and looking after your home visit here*

*Please note: The Torus website contains specific information for tenants and customers who are renting rather than shared owners or outright buyers, please do not assume all of the information on the site applies to you and your home. 

 Disclaimer: the image is just for reference.