Is a heated airer or a dehumidifier better for drying clothes?

A heated airer warms the washing; a dehumidifier removes the water from the room. The dehumidifier is the one that also protects the house from damp.

Difficulty: beginner
Time: 15 min
Read: 4 min

Short answer

A dehumidifier is the better single purchase for most homes, because it dries washing and removes the moisture from the air rather than releasing it into the room. A heated airer is cheaper and faster on its own, but it needs ventilation or a dehumidifier alongside it.

Drying a load of washing indoors releases roughly two litres of water into the house. That is the real question behind this comparison. A heated airer speeds evaporation, which puts that water into the air faster. A dehumidifier collects it. Which one you need depends on whether your problem is drying time or condensation.

What you'll need

An indoor airer
A power socket
A room that can be closed (optional)

Ways of drying washing compared

Step by step

Work out which problem you have.Washing takes two days to dry, or windows stream with condensation and there is mould on the walls. The first is a speed problem, the second is a moisture problem.
Understand what a heated airer does.Low-wattage heated bars warm the clothes so water evaporates faster. It costs a few pence an hour. It puts every drop of that water into the room air.
Understand what a dehumidifier does.It draws room air across a cold surface, condenses the moisture into a tank and returns dry, slightly warmed air. Clothes dry because the air around them is dry.
Compare running costs realistically.A heated airer typically draws 200 to 300 watts, a domestic dehumidifier 150 to 500 depending on type. Neither is expensive; both are far cheaper than a tumble dryer.
Consider the house as well as the washing.If you already have condensation, mould or a musty smell, a heated airer makes it worse and a dehumidifier makes it better. That usually settles the decision.
Use them together for the fastest result.Airer, cover, and a dehumidifier in the same closed room dries a full load in three or four hours. It is the best domestic alternative to a tumble dryer.
Close the room either way.A closed door concentrates the effect. With a heated airer, open a window in that room instead so the moisture goes outside rather than into the rest of the house.
Choose the dehumidifier type by temperature.Compressor models are efficient in a warm room but poor in an unheated one. Desiccant models work well in cold spaces such as a garage or an unheated utility room.
Empty and clean the tank regularly.Standing water in a dehumidifier tank grows bacteria and will start to smell. Empty daily in use and rinse the tank weekly.

Tips

A cover over a heated airer traps warm air around the clothes and roughly halves the drying time for a few pounds.
A dehumidifier also dries out a bathroom, protects a wardrobe on an external wall and helps a damp cupboard, so its usefulness extends well beyond laundry.
Spinning the load at a higher speed in the washing machine reduces the work for either appliance more than any setting on them does.

Common mistakes

Using a heated airer in a closed room with no ventilation — The water has to go somewhere. In a sealed room it condenses on the coldest surface, which is usually an external wall or a window reveal, and that is where mould appears.
Drying washing over radiators instead — It blocks the heat output so the room takes longer to warm, it costs more in heating than either appliance, and it puts the same moisture into the air with none of the control.

If it doesn't work

Condensation on windows after drying washing

Cause: Moisture released into the room with nowhere to go — Fix: Run a dehumidifier in the same room, or open a window in that room and close the door to the rest of the house.

Washing still damp after a night on a heated airer

Cause: Too much on the airer, or saturated room air — Fix: Spread the load out, cover the airer, and add ventilation or a dehumidifier so the air can accept more moisture.

Dehumidifier collecting almost no water

Cause: Room too cold for a compressor model — Fix: Warm the room, or use a desiccant model, which works down to low temperatures.

Musty smell from the dehumidifier

Cause: Standing water and a dirty filter — Fix: Empty and rinse the tank, wash the filter, and empty it after every session rather than letting water sit.

Questions people ask

Which is cheaper to run?

They are broadly comparable and both are far cheaper than a tumble dryer. The dehumidifier gives you moisture control as well, which is where the real value is.

Do I still need to open windows if I have a dehumidifier?

Yes, for air quality generally, but not while it is running for laundry — a closed room lets it work far more efficiently.

Will a dehumidifier stop mould?

It removes the moisture that mould needs, so it helps considerably. It does not fix a leak, rising damp or a cold bridge, which need addressing separately.