Calculators / Heating and cooling
What size dehumidifier do I need for my garage?
A garage under 2,000 sq ft needs 20 to 50 pints a day, depending on how damp it gets. Put in your size and you'll get the range, plus the old rating so you can read an older box.
Updated · How we check our numbers
You need
25 to 40 pints a day
That's for 576 sq ft, very damp (75 to 90% humidity). A 25 pint unit covers it. Before 2019 the same unit was sold as a 40 pint.
- Floor
- 576 sq ftunder 2,000 sq ft
- Capacity
- 25 to 40 pintsper day, 2019 test
- Old rating
- 40 pintsame as a 25 pint now
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Estimate for planning only, not professional advice. Check the manufacturer’s instructions, your local code and a licensed professional before you buy, build or install. Use at your own risk. Terms.
24 x 24 ft = 576 sq ft
very damp, under 2,000 sq ft = 25 to 40 pints a day (ENERGY STAR)
Sizes on the box
2019 test pints- 20 pintsold as 30 pint before 2019Too small
Under the 25 pint low end.
- 25 pintsold as 40 pint before 2019In range
Inside the ENERGY STAR range for your garage.
- 30 pintsold as 50 pint before 2019In range
Inside the ENERGY STAR range for your garage.
- 35 pintsold as 60 pint before 2019In range
Inside the ENERGY STAR range for your garage.
- 40 pintsold as 70 pint before 2019In range
Inside the ENERGY STAR range for your garage.
- 55 pintsold as 90 pint before 2019More than needed
Works, but you pay for capacity you won’t use.
Old ratings from ENERGY STAR’s conversion table.
Since June 2019 the test runs at 65°F, not 80°F, so the same machine gets a lower number. A unit sold as 50 pints back then is a 30 pint now. Make sure you compare the same test.
Nobody empties a bucket every day. Get one with a hose outlet and run it to a floor drain or out the wall, or buy one with a built-in pump.
See dehumidifiers with a pump on Amazon (opens Amazon in a new tab)The rating is measured at 65°F. A garage that sits colder than that will pull less water than the box says. Check the maker’s low-temperature limit before you buy.
How we work it out
The sizes come straight off the ENERGY STAR chart. It splits by how damp the space is and whether it's under or over 2,000 sq ft.
under 2,000 sq ft: moderately damp 20 to 30, very damp 25 to 40, wet 30 to 50 pints a day
over 2,000 sq ft: 30+, 40+ and 50+
Watch the rating on the box. In June 2019 the DOE test changed from 80°F to 65°F, so the same machine is rated lower now. A 30 pint unit today was a 50 pint unit before. We give both.
If water comes through the slab or the walls sweat, fix that first. No dehumidifier keeps up with a leak.
Where the numbers come from
Heating and cooling
Garage floors
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