Where to place a dehumidifier

Whether you’re tackling damp in one problem room, drying the laundry or dehumidifying your whole home, there’s an art – no, a science – to positioning a dehumidifier. We’ve asked the experts where, and how, to position a dehumidifier to get the very best results. That means which room to put it in and also where in the room to place it for optimal results.

If you’re not sure whether you have a humidity problem or if you even need a dehumidifier to begin with, don’t worry. We’ll also explain how to test for humidity, with the help of a couple of ice cubes.

Where should I place a dehumidifier?

Aneesa Khan, assistant home electricals buyer at VonHaus, recommends using a dehumidifier in a small room, with the doors and windows closed, so it can get rid of excess moisture faster. She adds: “If you are trying to target a particular spot, or you’re using it to help dry your laundry, ensure the fan (blowing the dry air out) is pointed the right way, so the air flow is more targeted.”

“One of the biggest mistakes people make when using a dehumidifier is putting them in the wrong location,” says Joshua Warren, air treatment expert at electrical retailer AO. “Most people tend to put them in a corner, when instead you should be positioning the dehumidifier in the centre of the room to remove moisture. This ensures that there is enough space around the dehumidifier for the air to circulate.”

Though Chris Michael, managing director of Meaco, adds: “Some dehumidifiers need to have 30cm of space around them for airflow but some models have been designed to be pushed directly against the wall saving space.”

That said, Michael is a big fan of using a single dehumidifier in the middle of the home: “If you purchase the right size dehumidifier, it will dehumidify the entire home. Moisture in the air will migrate towards it from every room. The best location for a whole-home dehumidifier is in a central area, like a hallway or landing.”

He adds: “Always keep the windows closed when using a dehumidifier, otherwise it will be trying to extract moisture from the outside world.” But he says nearby pet water bowls, fish tanks and toilets are just fine.

Where shouldn’t you place a dehumidifier?

“Dehumidifiers are not IP rated [meaning they haven’t been certified for resistance against things such as dust or water] and therefore cannot be put in the bathroom,” explains Chris Michael, managing director of Meaco. “They also can’t be put in a space smaller than 4m2 or near a heat source.”

Regulations dictate you’re not allowed power sockets in bathrooms for good reason and it’s not safe to run extension leads in there because of the water. But bathrooms do get damp, so a dehumidifier in the hall just outside is a great idea.

“’Can I use a dehumidifier in the bathroom?’ is the second most common question Meaco is asked after ‘What size dehumidifier do I need?’” says Michael. “The advice is ‘no’ from Meaco: it’s not safe to do so and there’s also no need to do it. The landing is the most common position to use a dehumidifier, with its proximity to the bathroom, bedrooms and access to the general airflow throughout the property.”

Which rooms are particularly susceptible to damp?

Think about where in your home you are having damp problems. “If your entire house is damp, start by placing your dehumidifier at the root of the problem,” says Joshua Warren. “Put your appliance in the area that is the most affected by dampness. For most houses, the common areas of dampness include bathrooms, kitchens and basements.”

Bathrooms and kitchens are naturally prone to moisture as a result of steam being created, so good ventilation is key and a dehumidifier can help tackle the problem. You can position one in the kitchen but, as mentioned above, not in the bathroom itself.

How to spot areas of high areas high humidity

Our article on when you should use a dehumidifier goes into more detail on this point. But put simply, look out for signs such as condensation on windows and doors, mould and mildew, a damp smell or clothes taking ages to dry. You might also notice bubbling paint or discolouration on the walls or ceilings.

You may also have a temporary damp issue resulting from a recently-plastered room or – in a much worse scenario – flooding, and need a dehumidifier to draw out the moisture fast.

How to test for humidity

Some dehumidifiers come with built-in humidity detectors but if you’re simply trying to figure out whether you need one or not, you can buy a moisture meter (hygrometer is the fancy word for it) or borrow one from a tool library.

“The most accurate way to test humidity levels is by using a hygrometer, but a handy home test for humidity is the ice cube test,” says Aneesa Khan. “Place a couple of ice cubes in a glass of water and wait five minutes. If the glass is dripping with condensation, this suggests humidity levels are very high. But, if there is no condensation at all, this could suggest the air is too dry. This test should not be done in a kitchen as cooking vapours could lead to unreliable results.”