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I’ve seen so many garages and workshops break down from issues related to high humidity. Most folks don’t even notice that their garage is slowly rotting away from the inside-out.
The worst part about high humidity in a space like a garage is that it often goes unnoticed until it’s too late.
That’s why it’s critical to have a humidity removal plan in place 24/7.
Using a garage dehumidifier will help prevent wood rot, mold growth, and other problems caused by moisture in the air.
In this article, I’ll review some of the best garage dehumidifiers that you can get online.
I’ll also discuss what features you should look for so you can keep your garage dry year-round in the easiest way possible.
Best overall garage dehumidifier
This Frigidaire dehumidifier is my pick since it's so easy to use. Its tank is effortless to empty. It also has a cord storage system built into the unit—so it's easy to move around.
The Frigidaire High Humidity 50-Pint Dehumidifier is the best choice overall for garage dehumidification. It provides up to 229 CFM airflow and 50 pints per day of dehumidification.
My favorite thing about this dehumidifier is its cord storage. There is a place to wrap the cord around and secure it on the back of the unit. This helps when moving the unit around your garage since the cord will stay out of the way.
The tank on this unit is easy to empty. It even has an indicator on its front, so you can see how full it is without touching it. This saves you time because you’ll be able to see exactly when it’s time to empty your dehumidifier.
If you don’t want to empty a tank every day, then it also has a built-in condensate pump for continuous draining. With a continuous drain setup, you’ll never have to worry about emptying the tank. So you can just set it and forget it!
- Easy to empty tank
- Cord storage on the unit for smooth transport
- Has a built-in condensate pump
- Pricey and hard to find online
Best overall garage dehumidifier: Runner-up
The GE 50-Pint Dehumidifier is a strong contender to my first choice, the Frigidaire 50-Pint. However, the GE model has a few shortcomings.
One thing is that it doesn’t have any place to wrap the cord on the unit. This means that the cord will be flailing around while you try to move the unit from one place to another. This is not a huge hassle, unless you’re moving the dehumidifier around your garage frequently.
Another shortcoming of this model is its handle placement. There are two handles that are recessed in the side of the dehumidifier. They are awkwardly placed and relatively shallow, so grabbing the unit by these handles makes it difficult to move around.
Even with all of these shortcomings, the GE Dehumidifier is a solid choice for a garage dehumidifier if you can get one for a good price.
- Includes a 16′ drain hose
- Slightly more compact than Frigidaire 50-Pint
- Has a built-in condensate pump
- No built-in cord storage
- Awkward handle placement
Best dehumidifier for a small garage
Most small garages won’t need a high-capacity dehumidifier to get the job done. In fact, a small dehumidifier such as the Frigidaire 22-Pint Dehumidifier is capable of dehumidifying most 1-car garages in warm conditions.
This dehumidifier has a built-in collection tank that you’ll need to empty once or twice a day.
If you’re looking for a long-term solution, you can hook up a drain hose to its drain spout on the back of the unit. However, it does not include a condensate pump, so you’ll need to use an external pump if you want to drain condensate upwards.
- Fits nicely on a shelf
- Tank is easy to empty
- Drain spout on the back of the unit
- No built-in condensate pump (but it has a drain spout for gravity draining)
Best mounted garage dehumidifier
If you’re the kind of person who wants a more permanent solution, then getting a mounted dehumidifier is the way to go.
The Aprilaire 1820 Pro Dehumidifier is designed for whole-house and crawl spaces, but can easily be deployed in a garage as well.
This dehumidifier can be hung from a ceiling to stay out of the way. This means that you’ll have more space for storage and tools.
With a 70-pint capacity, this dehumidifier is designed for larger areas.
If you are having trouble getting proper airflow coverage in your garage, then look into this unit. It has duct collars so you can attach flex ductwork for remote areas in your garage.
It also has a 5-year warranty– the longest warranty of any of the dehumidifiers I reviewed.
One of the drawbacks of this dehumidifier is that it does not have a tank or built-in condensate pump. So you’ll need to install a drain line to drain condensate into an external collection tank or outside your garage.
- The strongest dehumidifier in our roundup: 70-Pints!
- Can be mounted and ducted to dehumidify a large garage
- 5-year warranty
- No built-in tank or condensate pump
- Very heavy unit– only good for permanent installation
What features should you look for in a garage dehumidifier?
Before looking for a garage dehumidifier, you’ll need to figure out what your needs are.
The size, capacity, and drainage system are the three most important factors that you need to consider when purchasing a dehumidifier.
Below I’ll discuss what features you need to look for in a garage dehumidifier.
Find a dehumidifier that is the right size
There’s no point in getting a huge dehumidifier with all the bells and whistles if it can’t fit in your garage.
Sometimes all you need is a modest, small-sized dehumidifier to do the trick. If your garage is a small 1-car garage, chances are that a large 50-pint unit has too much capacity anyway.
You also need to consider portability. If you’re only going to be using a dehumidifier for part of the year, you’ll want a dehumidifier that has at least SOME portability. That way you can move it into your garage when it’s needed, and then move it to storage when the wet season is over.
Find a dehumidifier that has the correct capacity
The capacity (measured in pints or pints per day) is a rating of how much moisture a dehumidifier can remove from the air in a single day.
For instance, a dehumidifier with a capacity of 40 pints is capable of removing up to 40 pints of water from the air in a 24-hour period.
You’ll only get a dehumidifier’s rated capacity at the conditions that it was tested at. So that 40-pint dehumidifier is definitely not going to remove 40 pints per day when the temperature is a brisk 60°F and the relative humidity is only 50%.
Most manufacturers follow dehumidifier testing procedures set forth by the Association of Home Appliance Manufacturers.
AHAM DH-1-2017 is the most recent version of the testing standard. However, you’ll find that many dehumidifiers on the market today were tested using the older 2008 standard (which is OK… just be sure that your dehumidifier was tested using some version of the standard, or else its rating might as well be made up).
In most cases, you won’t get the full-rated dehumidification that is advertised. Just know that you’re being provided a baseline for comparing dehumidifiers against one another.
Find a dehumidifier that has the drainage system you need
Generally, there are two different types of drainage systems in dehumidifiers:
- Collection tank
- Continuous drain
The default setup in most portable dehumidifiers is a collection tank. The tank is built into the dehumidifier and collects moisture that is removed from the air.
A continuous drainage system usually consists of a hose thatʻs connected to the dehumidifier. The hose serves as an outlet that lets the dehumidifier continuously empty its moisture into a drain, or anywhere outside of the room.
If the drain is at a lower elevation than the dehumidifier, then that’s no problem– gravity will do the trick.
If you need to drain moisture upwards in elevation, then you’ll need a pump to do that.
Some of the larger dehumidifiers (such as the Frigidaire unit we reviewed) have a built-in condensate pump that takes care of this. So you can just connect a hose to the dehumidifier’s discharge and direct it wherever you want to drain the moisture.
Some dehumidifiers don’t have a built-in tank or built-in pump. If that’s the case, then you’ll need to either:
- Drain the condensate through a hose by gravity
- Drain the condensate into an external tank
- Install an external pump to continuously drain the condensate upwards or a long distance
Most whole house and crawl space dehumidifiers don’t have built-in tanks or built-in pumps. The reason for this is because these types of dehumidifiers assume that some level of installation must be done. So you’ll be installing the dehumidifier and a properly-sized pump anyway.
What size dehumidifier should you use in your garage?
When selecting the correct size dehumidifier for your garage, bigger is better, right? Not always.
I’ve seen many folks get a huge humidifier for their tiny garage, then wonder why their electricity bill spikes up.
On the flip side, some people think that they can get away with using one of those tiny countertop humidifiers for their 2-car garage.
The truth is that there is a happy medium between humidifier capacity and garage size.
To find the correct capacity dehumidifier for your garage, you’ll need to take these factors into account:
- The size of your garage
- The relative humidity in your garage
- The temperature in your garage
Let’s dive in further to discuss each of these factors.
How to choose a dehumidifier based on the size of your garage
The size of your garage is the most obvious factor to take into account when selecting a dehumidifier.
Simply put, a larger garage will require a larger dehumidifier.
The energystar.gov website splits up recommended dehumidifier capacities based on square footage. They specify spaces under 2000 sq. ft. as small-medium, and spaces over 2000 sq. ft. as large.
The main takeaway is that spaces over 2000 sq. ft. will require more dehumidification capacity than spaces under 2000 sq. ft.
However, 2000 sq. ft. shouldn’t be considered the absolute cutoff. If your garage is near the cutoff, then you should opt for the next size.
For instance, if you have an 1800 sq. ft. garage, then you should get something near the higher-end of recommended capacity.
How to choose a dehumidifier based on the humidity in your garage
Besides the size of your garage, the other big factor is the relative humidity inside your garage.
The relative humidity level in the space that you need to dehumidify plays a huge factor in the capacity of the dehumidifier that you should choose.
For instance, a small space with high humidity will require more dehumidification capacity than a large space with low humidity.
In the end, it’s a good idea to go with a higher-capacity dehumidifier if you are unsure. You don’t want to get a brand new dehumidifier only to find out that it doesn’t reduce the humidity as much as you need it to.
If you will be using your dehumidifier in a cold garage, then there is one final factor to consider that we’ll discuss below.
How to choose a dehumidifier based on the temperature in your garage
The final factor to consider when selecting a dehumidifier is the temperature inside your garage.
If your garage gets cold, then your dehumidifier’s performance will suffer. For instance, a dehumidifier that is rated for 30 pints might only be capable of 20 pints at lower temperatures.
Worse yet, frost can form on the coils inside your dehumidifier while operating at low temperatures.
Many dehumidifiers on the market today have built-in frost sensors that will shut down the dehumidifier if frost forms on the coils. In this case, the dehumidifier will turn off to let the ice thaw out before it turns back on.
Most dehumidifiers with the ENERGY STAR label are rated to be used at temperatures as low as 42°F. But you should check with the manufacturer to confirm that the model you purchase is capable of performing at low temperatures if that is what you are going to use it for.
What causes moisture in a garage?
If you have moisture issues in your garage, understanding the source of moisture will help you combat the problem.
Below, I’ll discuss a few common sources of moisture in the garage.
Moisture in the garage from a cold floor
During the spring and summer months, the concrete slab in your garage tends to stay fairly cool. However, a cold garage floor can be a target for moisture.
As the warm air in your garage interacts with a cold concrete slab, moisture will form.
This effect is noticeable especially during the spring months. As the warm, moist air comes into contact with a cold garage floor, water condenses on the floor.
Fortunately, there are some simple remedies for this problem.
Using a dehumidifier in your garage is the most obvious solution. A dehumidifier will remove moisture from the air, so water won’t condense on your garage floor.
Besides directly removing moisture from the air in your garage, there is also an indirect solution to this problem– a garage heater.
Using a heater to warm up the floor in your garage will prevent water from condensing on it.
How does a warm garage floor prevent water from condensing on it? It’s all about the dew point.
The dew point of air is the temperature at which moisture will begin to form as droplets on a surface.
When the floor of a garage is cold, the warm air in the garage begins to cool near the floor’s surface. Since cold air cannot hold as much moisture as warm air, the moisture escapes from the air and collects on the cold floor.
Water seeping in from outside the garage
Sometimes, water can infiltrate your garage directly from the outside.
If you notice that the floor of your garage gets wet, then it may be caused by one of the following:
- Water seeping in from underground. This happens when there is no vapor barrier between the garage slab and the ground.
- Water seeping in from the walls. This happens when part of the garage is below grade.
Keep an eye out for water in your garage, especially when it rains. Cracks in the floor provide a space for water to infiltrate your garage.
Gaps in between the slab and the walls in the concrete also provide a space for water to seep in.
If you see water coming into your garage from these cracks, then using a professional-grade sealant will help keep moisture out.
Water from vehicles and laundry
Sometimes a garage gets humid from the things that you bring in there.
Parking a wet car inside your garage on a rainy day will bring moisture directly into your garage.
Likewise, hanging up laundry to dry in your garage will cause a spike in humidity levels.
Water from heaters and HVAC system
An often overlooked source of water in the garage is water from appliances. If you have one of these appliances in your garage, then it could be a source of moisture:
- Water heater
- HVAC system (air conditioner or furnace)
Water heaters are a common source of excess moisture. If they are leaking, water heaters can spill water onto the floor of your garage.
Another source of water from appliances is condensation. During the hot summer months, water can form on the cold water piping that goes into your water heater.
Condensate from your HVAC unit is another source of moisture. During the summertime when your AC is running, condensation from the drip pan or drip line can overflow into your garage.
If your ductwork is not insulated, moisture could also form on it. Cold ductwork interacting with warm air will cause condensation to form and drip off. Be sure to check that all your AC ductwork is properly insulated and sealed so air cannot interact with it.