Damp & Condensation

Condensation is the main cause of damp or mould in your home which can cause a great deal of damage. 

You are responsible for reducing the condensation in your home and any mould caused by the condensation. You must also clean away any mould if it is allowed to build up.

You can lower the levels of condensation in your home by making a few easy changes to the way you use your home, as highlighted in this short video.


You can also read below or view our easy to print PDF about condensation in your home.

What is condensation?

There is always some moisture in the air inside your home. Everyday activities, especially cooking, washing, having a bath or shower and even breathing causes this moisture .

Condensation is caused by the moisture in the air. When the air gets cold, the moisture condenses to form water droplets, or condensation. You can often see this on your windows in the morning.

What is mould?

Condensation can cause black mould on walls, clothes, and furniture. This may look unpleasant and have a musty smell. In really bad cases, condensation can damage plasterwork and rot wooden window frames. Airborne spores may also spread the mould to other areas of your home.

Mould often appears in places where the air doesn't move much, so you should regularly check in corners, on or around windows and behind wardrobes, sofas and cupboards for signs of mould and clean it away throughly as soon as you see it.

How to reduce condensation and mould


The best way to reduce condensation and mould is to make sure your home is well ventilated with plenty of air circulating. You should:

Make sure you always use the extractor fan in the bathroom or kitchen if there is one fitted.

Leave a window or door open when cooking or having a bath or shower to allow the moist air to escape from your home.
Try and have at least one window slightly open for most of the time – fresh air is good for everyone and reduces condensation and mould. Please remember to keep your home safe and secure, make sure you close windows when you go out and open them when you are at home.

If you have a tumble dryer this should be directly vented to the external of the building and not the inside of your home.

Make sure you dry your windows, windowsills and all surfaces made wet by condensation each morning (especially in the kitchen and bathroom). To avoid more condensation forming, wring out the cloths used for this and do not dry them on a radiator or heater.

Make less moisture

If there is less moisture in the air in your home, there will be less condensation. There are simple things you can do to reduce this:

Put a lid on saucepans when cooking to keep the steam in.

If you can, hang your laundry outdoors. This will make it smell lovely too!

If you can’t hang your washing outside, the best place to dry it is in the bathroom. Make sure you close the door and leave the extractor fan on or window slightly open whilst it's drying.

Keep warm

Keeping your home warm can reduce condensation, as warm air holds more moisture than cold air.

It is usually better and cheaper to have the heating on low all the time instead of short bursts of high heat.

We appreciate heating your home can be costly and keeping the heating on when you are out might seem a waste. But, if you keep the heating on low all the time, your boiler will not have to work as hard to reheat the home each time each it switches on, making it more efficient and economical.

If you would like advice about the costs of heating your home please contact the Energy Saving Trust on 0300 123 1234 or www.energysavingtrust.org.uk

Treating mould

You can remove small patches of mould with a fungicidal (mould-removing) wash. You can buy these cheaply from most large supermarkets or DIY shops. Please make sure you follow the product safety precautions carefully. You need to use a specialist product as soap and washing up liquid are not effective in killing mould.

You need to throw away the cloths you have used to clean the mould with, as they hold the spores. Wash and dry any mildewed (mouldy) clothes and shampoo carpets and sofas. Don't try to remove mould with a brush or vacuum cleaner, as this will make spores airborne and spread them further around your home.

If you need to redecorate after treating mould you will need to use fungicidal resistant paint and wallpaper paste to prevent the mould returning.

Structural (rising and penetrating) damp

What looks like ‘damp’ in walls and ceilings is normally caused by condensation. But there may be other causes:

Leaking roofs, guttering or chimney flashing (penetrating damp).

Leaking internal and external pipes (penetrating damp).

Faulty damp-proof course, rendering or brickwork (rising damp)

Damp can be recognised by the discolouration of internal walls or ceilings, the presence of tidemarks or salt deposits. It can also be identified by blown or blistered plaster (which sounds hollow when gently tapped) and rusty nails in skirting boards and floor timbers. Random damp patches to the walls and ceilings (at any height) may appear. If you think this has happened in your home then report this to us.

Please note while the structure of the building is our responsibility, if the issue is condensation then it is your responsibility to air your home and clean the mould.

How to treat and prevent structural damp

Penetrating damp should be treated by finding the reason for the water coming in and where it is coming in (e.g. a loose or cracked roof tile, or crack around a window) and undertaking maintenance repairs. Once the repair is complete, damp areas need time to dry naturally before being redecorated. Please note this could take several weeks.

Rising damp needs to be assessed by a professional surveyor and they will assess what work is needed. This may include re-plastering, rendering, waterproofing and renewing the damp course, or increasing drainage. You must make sure there are no items leaning against any external wall, including soil, rubbish, mattresses, wood and temporary structures.

Condensation Leaflet