Drying washing indoors puts all the water from the clothes into the air, and without ventilation it ends up as condensation and mould on cold surfaces. If you must dry clothes inside, do it in one room with the door shut and either a window open, an extractor fan or a dehumidifier running.
I’m not going to pretend everybody can dry their washing outside. Half the year in Yorkshire it’s raining, and plenty of people live in flats without a garden. But it’s worth understanding what happens when you dry a load on the radiators.
All the water you can see and feel in a wet load of washing has to go somewhere. When clothes dry indoors, that water evaporates into the air of your home. The warmer the room, the faster it happens. Then that moist air moves around the house until it finds a cold surface, a window, an external wall, the back of a wardrobe, and turns back into water. Do that several times a week through winter and you’re feeding condensation and mould.
If you have to dry indoors
- Use one room, ideally a bathroom or utility room with an extractor fan, or a small room where you can keep the door shut.
- Ventilate that room: window open a little, extractor fan on, or a dehumidifier running in there with the door closed. A dehumidifier with a laundry setting is genuinely useful for this.
- Avoid drying on radiators. It makes the radiator less effective at heating the room and pumps moisture straight into the warmest air.
- Don’t dry washing in bedrooms, especially overnight.
- Spin the washing well first so there’s less water to deal with.
Tumble dryers
- A vented dryer must have its hose going outside, through a wall or window. Venting into the room or a cupboard defeats the object.
- Condenser and heat pump dryers collect the water in a tank or send it to a drain, so empty the tank and clean the filters regularly.
Drying clothes indoors isn’t the only cause of condensation, but in a lot of the homes I survey, especially smaller properties, it’s a big part of it. If you’re fighting mould, changing how you dry washing is one of the quickest wins you’ll get.
For landlords, it’s worth remembering that tenants need somewhere practical to dry washing. Providing a vented dryer space, a good extractor fan or a drying area helps prevent the problem in the first place.
When to call a specialist
If you've changed how you dry clothes and still have condensation and mould, the property may need better ventilation. A condensation survey will show where the moisture is coming from. Book a survey with All Dry on 01226 287181 or email info@alldrydampproofing.com.
Listen on The Damp Show
Frequently asked questions
Does drying clothes on radiators cause mould?
It can, because the water from the clothes goes into the air and condenses on cold surfaces elsewhere.
What's the best way to dry clothes indoors?
In one room with the door shut and a window open, an extractor fan or a dehumidifier running.
Can a vented tumble dryer vent indoors?
No, the hose must go outside or the moisture just goes into your home.