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Quick answer
A compressor dehumidifier with a laundry mode dries a typical load indoors in roughly 4–8 hours. Put the airer and dehumidifier in a small room with the door and windows closed, leave a gap between clothes, and place the unit about a metre away. Choose 12L for occasional loads and 20L if you dry washing most days or for a family.
Drying washing indoors is unavoidable for a lot of UK households — no garden, no tumble dryer, or just the British weather from October to April. The problem is where the water goes. After a normal spin, clothes typically still hold roughly half their dry weight in water — so a 4–5kg load can carry around 2 litres or more. As it dries, all of that goes into the air, and without somewhere to go it ends up on your windows and walls. GOV.UK’s damp and mould guidance lists drying laundry alongside showering and cooking as everyday activities that build up moisture indoors.
A dehumidifier solves both problems at once. It dries the clothes faster and pulls that moisture out of the air before it becomes condensation.
Why not just use the radiators?
Drying clothes on radiators is common, but it’s one of the worst options for damp. The moisture goes straight into the room, the clothes block the heat from reaching the room (so the boiler works harder), and the damp air drifts to colder rooms where it condenses. Many councils and housing associations specifically advise against it. If you’re comparing options on cost, see dehumidifier vs tumble dryer vs heated airer.
The set-up that works
Pick the smallest room you can close off — a box room, utility room, or even a large bathroom with the dehumidifier placed safely outside the door if there’s no suitable socket (see dehumidifiers in bathrooms).
Close the door and windows. The dehumidifier then only has to dry that small volume of air.
Spread the washing out. Leave a few centimetres between items; hang shirts on hangers; turn thick items halfway through.
Place the dehumidifier about a metre from the airer, with its outlet pointing towards the clothes if it has a louvre. Don’t let clothes cover the air intake.
Use laundry mode if it has one — or set the humidity to its lowest setting and fan to high.
Check after 3–4 hours. Turn or move anything still damp.
How long does it take?
Usually 4–8 hours for a normal load. It depends on:
The fabric — synthetics and cotton shirts dry fast; towels, jeans and hoodies are slowest.
How crowded the airer is — the biggest single factor you control.
Room size and temperature — a small, mildly warm room is ideal.
The dehumidifier’s capacity — a 20L unit is noticeably quicker than a 10L one.
Many laundry modes run at full power for a set time (often around six hours) and then switch off, which makes overnight drying easy.
How we choose: these are types of product matched to the criteria in this guide, not individually tested models. Check current specifications and reviews before you buy.
Running costs
A compressor dehumidifier in laundry mode typically draws around 150–300W for a 12L model and more for a 20L. A five-hour session at 250W uses 1.25kWh — about 33p at the October–December 2026 price cap rate of 26.32p per kWh. Our running costs guide has a calculator for your own tariff.
Keep an eye on the rest of the house
If you dry washing indoors regularly, a cheap hygrometer on Amazon (opens in a new tab)(paid link) in the laundry room and a bedroom shows whether moisture is escaping. Readings creeping above 60% elsewhere usually mean the door is being left open, or the dehumidifier is too small for the amount of washing. Our guide to how to use a dehumidifier covers placement and settings in more detail.
Frequently asked questions
How long does a dehumidifier take to dry clothes?
Typically 4–8 hours for a normal load in a small closed room, depending on the fabric, how full the airer is, the room temperature and the size of the dehumidifier. Thick towels and jeans take longest; spreading items out makes the biggest difference.
Is it cheaper to dry clothes with a dehumidifier than a tumble dryer?
Usually, yes, compared with vented and condenser tumble dryers, and it's similar to a heat pump dryer. A compressor dehumidifier drying a load over several hours typically uses around 1–2kWh. See our full comparison for the numbers.
Should the door be open or closed when drying clothes with a dehumidifier?
Closed, along with the windows. The smaller and more enclosed the space, the faster the clothes dry and the less moisture spreads to colder rooms where it would condense.
Can I dry clothes with a desiccant dehumidifier?
Yes. Desiccant models blow slightly warm air, which helps in a cold room or unheated utility space. In a heated home a compressor model with laundry mode is cheaper to run.
Does drying clothes indoors cause damp?
It can. A spun load of washing can still hold a couple of litres of water, and it all goes into the air as it dries. Without a dehumidifier or good ventilation that moisture ends up on windows and cold walls, which can lead to condensation and mould.
How dehumidifiers, tumble dryers and heated airers compare for drying clothes in a UK home — running cost per load at current prices, speed, damp and upfront cost.
What the litre rating on a dehumidifier really means, and how 10L, 12L, 20L and 25L models compare on capacity, size, noise, tank and running cost in UK homes.
Where to place a dehumidifier, whether doors and windows should be open or closed, what humidity to set, and how long to run it for condensation, damp and laundry.
