A woman emptying a dehumidifier

The laundry you hang to dry stays damp for ages, there’s condensation on the inside of your basement windows or a musty odour clouds the air. Do any of these scenarios sound familiar? If yes, your house may have a humidity issue. But don’t worry—a dehumidifier can go a long way to helping you lower the moisture level in your home while you figure out the root cause of the problem. Read on for more about dehumidifier uses and benefits, plus how to buy one that works for your family.[1]

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1Do you need a dehumidifier?

There are a few telltale signs that you need a dehumidifier. Water stains, foggy windows and mould spots on walls and ceilings (eek!)—are the most obvious clues. But a consistent musty smell, food that seems to go mouldy more quickly than it should and even allergy symptoms in family members may indicate that you need to get the moisture out of the air.[2]

  • When to buy an air purifier instead: A dehumidifier pulls moisture out of the air, while an air purifier traps pollutants and filters them out. In some cases, you may need both an air purifier and a dehumidifier (for example, when you need to manage and remove mould spores from the air). But if moisture isn’t an issue and you’re just looking to improve the air quality in your home, an air purifier is likely the better bet.[3] Check out our air purifier guide to find one that works for you.
  • When to buy an air conditioner instead: An air conditioner will remove a bit of moisture from the air as it cools a sticky, hot environment, but it won’t solve a straight-up moisture issue. That said, some air conditioners have the ability to switch between AC and dehumidifier modes, so you may be able to get the best of both worlds.[4] Our air conditioner buying guide can help you find a model that works for you.
  • When to buy a humidifier instead: A humidifier adds moisture, which can be helpful in extremely dry climates, while a dehumidifier removes moisture. Both have their place in improving the air quality in your home; adding moisture to dry air can help with breathability while removing moisture can help to manage irritating mould and mildew.[5]
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Quick Tip
Running a dehumidifier at the same time as an air conditioner can help the air conditioner to run more efficiently because it won’t have to remove as much moisture from the air before cooling.[6]

2How does a dehumidifier work?

Dehumidifiers draw warm, humid air into the unit, which then cools the air to remove the moisture. The newly dried air is then pushed back out into the room by a built-in fan.

  • Portable dehumidifiers: In small, portable units, the water collects in a removable basin that you’ll need to empty regularly. Some portable units can drain directly to a washtub or the outdoors, depending on the unit’s location.
  • Whole-home dehumidifiers: In “whole home” solutions installed by an HVAC professional, the water is expelled from the home.

Shop Best-Selling Dehumidifiers

3What are the main dehumidifier benefits?

Dehumidifier in a closet PureGuardian’s Small Space Dehumidifier may reduce the musty odour in your closet or laundry room.

There are many benefits to reducing the moisture in your home, from helping to preserve the structural integrity of your house to improving the everyday comfort of your family.

  • Improve air quality: Reducing the humidity levels means that your house is less likely to harbour allergens like dust mites, mould and mildew that can wreak havoc on your breathing.[8]
  • Reduce odour: If an area of your home has a musty, damp smell, moisture is often the culprit.[9] Taking down the moisture will help you eradicate funky aromas.
  • Prevent moisture damage: A dehumidifier can help with water damage, like warping and rotting floors and walls.[10]
  • Increase longevity of products, from food to electronics: Too much moisture can cause exposed food (cereal, bread) to spoil faster. It can also cause clothing to stay damp and develop smells, and electronics and tools to corrode more quickly.[11]

4What size of dehumidifier should you get?

When deciding what size of a dehumidifier to buy, the room’s size and moisture level are the most important considerations. A dehumidifier’s unit capacity is measured by the number of pints of water it can remove from a room in 24 hours.

Dehumidifier Sizing (2020)[12]

Space (square feet) Moderately Damp Very Damp Wet
300 20 pints 25 pints 25-30 pints
500 25-30 pints 30 pints 35-40 pints
800 35-40 pints 45 pints 45-50 pints
1,200 50 pints 55 pints 60 pints

Add five pints if multiple people live in or use the space, there are plenty of windows and doors or there’s a washer and dryer nearby. Add 10 pints if you live in a humid climate.

If you’re still unsure of what size unit to buy, opt for a larger model and run it on a lower setting.

5What other features should you consider?

After capacity, there are a few other features you might want to look for when purchasing a dehumidifier.

  • Humidistat: A built-in sensor that measures the humidity in the air and adjusts the dehumidifier’s performance means you’ll always address the correct moisture level.
  • Drain-hose connection or built-in pump: If you don’t want to be on the hook for manually emptying the unit’s water collection, look for a product with a drain hose connection so it can be configured to empty directly into a drain. Another option is a built-in pump that runs to a drain or directly to the outdoors.
  • Automatic shut-off: Some models have an auto shut-off feature. When frost forms on the coils, the dehumidifier will shut off to prevent improper operation and save energy.
  • Multi-speed fan: Having a fan that will run at a slower speed in a less-humid environment saves energy (plus you’ll deal with less noise).
  • Castor wheels: You’ll be able to easily move the dehumidifier where it’s needed most.[13]

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