Is a Dehumidifier Worth It? Running Costs and When It Helps

General buying advice. Always check current specifications, prices and reviews with the retailer before you buy.

A dehumidifier can make a damp, condensation-prone home feel drier and fresher, but it is not right for every problem. Here is how to decide whether it is worth it and what it might cost to run.

When a dehumidifier can help

It can reduce condensation on windows, help clothes dry indoors in winter, and ease the musty smell of a room that stays humid. It tends to be most useful in rooms that are lived in and have everyday moisture from cooking, showers and drying laundry.

When it will not fix the problem

A dehumidifier treats the air, not the cause. If damp comes from a leak, a faulty gutter, a failed damp-proof course or a building fault, it will not solve it. It also works best with doors and windows closed, so it is not a replacement for good ventilation.

Working out the running cost

You can estimate the cost yourself. Take the power rating in watts, divide by 1,000 to get kilowatts, then multiply by the hours it runs to get kilowatt-hours. For example, a 300 watt unit running for 5 hours uses 1.5 kilowatt-hours. Multiply that by your electricity unit rate, which is on your bill, to see the cost. A humidistat helps because the unit only runs when it needs to.

Get more from it

Keep doors and windows closed while it runs, leave space around the unit so air can flow, and empty or drain the tank regularly. Place it where the air is damp rather than hidden in a corner behind furniture.

Look at ventilation first

Using extractor fans, putting lids on pans, opening a window briefly after showering and drying clothes in a ventilated room can all reduce moisture. Sometimes that is enough, and it costs nothing.