Excess humidity in the garage? If you’re not sure, perhaps answering these questions will help.
- Does the garage floor feel wet and slippery?
- Do you notice standing water inside the garage after a day or two of a rainstorm?
- Is there frequent condensation or “sweating” on the garage floor? How about in the garage door?
- Have you seen any evidence of mold or wood rot on the corners of garage walls and ceiling?
- Have you noticed a musty smell whenever you open the garage door or whenever you spend time working inside?
If you answered ‘yes’ to all these questions, there’s one problem you need to deal with – excess humidity.
These signs aren’t as uncommon as you may think, especially with the lack of proper ventilation in the area. Without any way for the humidity to escape from the room, moisture will eventually build up. Over time, high humidity levels in the garage can cause devastating results.
Ideally, the first plan of action is to reduce humidity in the garage. So, would a dehumidifier deal with high humidity levels in the garage?
The short answer is yes – getting a garage dehumidifier is the most direct way to get rid of excess humidity and keep the moisture levels inside the garage in check.
Do Dehumidifiers Work in Garages?

What’s the simplest way to get rid of high humidity in the garage? A dehumidifier.
Your garage is supposed to be a well-sealed room but isn’t often very good at regulating temperature. Since garages are typically designed without windows, vents, or other outlets, garages don’t naturally promote proper ventilation.
So, with no way for air to flow freely, moisture will eventually build up. You can start seeing signs of excess humidity in the garage like “sweat” spots in the walls and floor and musty odor, or worse, standing water around floor corners, apparent mold growth, and wood damage.
Not to mention, high humidity can damage not only the garage structure but also the tools, equipment, furniture, and all sorts of things store in your garage.
Unless you want to make it a vast and costly garage project and add a few windows in your garage for ventilation, running a dehumidifier is the next best solution. The best dehumidifier for a garage controls the moisture inside the room. It transforms wet air into dry, warm and air free of excess water.
Still not sure about getting a dehumidifier for a garage? Here are a couple of advantages of getting one.
- Prevent mold and mildew growth, which happens in damp environments like a highly humid garage.
- Protect the garage’s wooden floor, walls, and ceiling from rotting and decay due to excess moisture in the air.
- Eliminate stuffy and damp indoor air and get rid of pollutants like pollen and dust mites.
- Protect your tools, car, machine, and other equipment from rusting caused by high humidity levels in the room.
Will a Dehumidifier Work in a Cold Garage?

A garage dehumidifier is the most straightforward answer to prevent high moisture inside the garage, thereby preventing mold, fungi, and corrosion. But here’s the thing – not all dehumidifiers work efficiently if the garage space is cold.
When you get the right one, it can undoubtedly get the job done on managing your garage’s humidity levels. But getting the wrong dehumidifier means you’ll be racking up on electricity without even reducing moisture.
Most garage dehumidifiers state their minimum operating temperature. Using them beyond that range in a cold garage will result in the unit’s coils freezing over.
So, are there dehumidifiers that can work in a cold garage? Thankfully, yes, some dehumidifiers can work in cold temperatures, like:
- Desiccant dehumidifiers
- Compressor dehumidifiers with special/automatic defrost functions.
But remember, they still won’t be as effective against humidity in a cold garage as advertised.
The truth is – dehumidifiers lose their capacity by half or so when there’s a noticeable drop in temperature.
As a rule of thumb, when buying a dehumidifier for a cold garage, go for units that claim they can cover larger space than what you have.
At What Temperature Do Dehumidifiers Stop Working?

Besides the room capacity a dehumidifier can handle, their user manuals will also indicate the unit’s minimum operating temperature.
Typically, garage dehumidifiers, if you are using a compressor dehumidifier, will work at 65-degrees Fahrenheit. Running the unit beyond that operating temperature will make it inefficient, working less than its advertised operating capacity.
In other cases, operating dehumidifiers under extremely low humidity conditions, like temperatures below 40 degrees, will render them ineffective altogether.
At these temperatures, evaporator coils may start freezing. When that happens, the dehumidifier will continue to run, racking up on electricity, but it won’t be getting rid of moisture from the air. In short, you’re paying for electricity without the unit dehumidifying the garage.
Unless you defrost the system or have an auto-defrost function, dehumidifiers will be useless when used under extremely low temperatures.
How Do I Stop My Garage from Getting Mold?
There is no more simple way to say this but keeping moisture out of the garage is the single best way to avoid mold growth. After all, allergy triggers like mold thrive in a humid environment.
Controlling the humidity inside the garage – through proper ventilation, heating, and insulation – will eliminate excess moisture that can lead to mold when it comes in contact with surfaces like walls and the ceiling.
- Fix roof leaks and broken pipes
- Clean up floods and spills
- Regularly empty the evaporation trays in air conditioners if your garage has one.
Putting a dehumidifier in a garage is another way to suck moisture from the air. With reduced humidity levels, your garage will be less hospitable to mold and mildew.
Do I Need to Put a Vapor Barrier in My Garage?
Vapor barriers help prevent moisture buildup, especially on the garage walls, ceiling, and crawlspaces. In some areas, particularly in colder climates, vapor barriers are a necessary part of building construction. They are also likely required if your garage building uses many porous materials.
But if you live in warmer climates, installing moisture barriers isn’t often required. If you need to reduce your garage’s humidity levels, running a dehumidifier will usually answer the problem.
What Size Dehumidifier for Garage to Get
So, we’ve established that setting up the best dehumidifier for the garage will eliminate excess humidity and prevent any more problems. But how do you select the best dehumidifier for a garage?
One of the primary factors to consider when getting a dehumidifier for a garage is proper sizing. Yes, the size of your garage dehumidifier matters a lot. After all, the size of a dehumidifier defines its total moisture removal capacity – in pints per 24-hour period.
Sizing the unit too small won’t be effective in controlling moisture inside a larger garage. On the other hand, oversizing your dehumidifier will also have a downside, like turning the system on and off more frequently than you should.
Sizing a dehumidifier for a garage is based on two things: garage size and garage conditions.
Start by asking: “how damp is your garage?”
- Slightly damp – air inside the garage feels slightly heavy
- Moderately Damp – has an occasional musty odor
- Very Damp – wet spots appearing on the garage floor and walls
- Wet – with seepage on garage floor and wall; apparent mold growth
Ready to size your garage dehumidifier? You can use the sizing guide below.

The number in these recommendations represents the smallest dehumidifier you need for the garage. But when in doubt, choose the best dehumidifier that can cover a slightly larger moisture category or square footage.
Considering the below factors will also help in getting the ideal size of your garage dehumidifier.
- If you are in a humid environment, add 10 pints.
- If you have a washer and dryer in your garage, add 5 pints.
- If your garage has multiple windows and doors, add 5 pints.
- If you are entertaining visitors inside the garage or if multiple people will spend time inside, add 5 pints.
Where Should You Place a Dehumidifier?

Garage dehumidifiers extract moisture in the air, and ideally, you’d want to place them in areas where they can efficiently suck in the damp air.
Generally, you only need to consider these three factors when figuring out where to position a dehumidifier in the garage.
1. Where is the humidity coming from?
Placing the garage dehumidifier at the primary source of humidity in the room is the most efficient choice. This way, the unit can capture the damp air before it gets a chance to infiltrate and damage other areas in the garage.
2. How big is the garage?
If you have a small garage, where you place the dehumidifier isn’t as important as there is less area to cover. But for larger garages, the ideal location for the unit is the central space where it can get maximum coverage.
3. Is anything blocking the airflow in and out of the dehumidifiers?
Dehumidifiers need clearance to maintain airflow and function properly. It means that the ideal position for the unit is somewhere not too close to the wall, furniture, or any other objects that can restrict airflow.
How Do I Keep the Humidity Out of My Garage?

To manage the humidity in your garage, you need to control the conditions that may be causing excess moisture inside the room. If ignored, the excess moisture may lead to more problems and bigger headaches later on.
Are you dealing with a lot of moisture in the garage? When your garage’s humidity situation goes out of hand, getting a dehumidifier for a garage will get rid of the problem for good.
However, other practical ways will help remove excess humidity in the garage.
- Allow Proper Ventilation – Opening the garage door, or windows if you have one, will help move the trapped, humid air out once in a while. If you don’t want to open the door for security reasons, running a portable fan will also improve the airflow and blow out excess moisture.
- Check for Leaks and Broken Pipes – Leaks in the roof and walls, including broken pipes, can draw water into the garage. So, check and repair any problems before it causes more damages.
- Organize the Clutter – Cluttered items in your garage restricts airflow and will eventually lead to condensation building up inside. Keeping the garage organized should help promote better airflow.
- Dry the Car Before Parking – If you park your car inside the garage after getting drenched in snow or rain, moisture will evaporate and build up inside the garage. So, before you park and close the garage, make sure to dry the car first.
Wrapping Up
Garages can become humid because of many reasons: outside climate, indoor temperature, leaks, spills, and not enough ventilation. Having a garage dehumidifier is the best way to keep the humidity levels in check.
Our top pick for the best garage humidifier would be the Vremi Moisture Maniac 22-Pint Dehumidifier. It’s a little machine that can dehumidify and purify a massive 1,500 square foot garage – a hybrid of sorts. It’s also energy-efficient and remains efficient even during cold temperatures, thanks to its Auto-Defrost function.
There are many bigger garage dehumidifiers out there if you require a bigger capacity than 22-pints/day, but we found this one suitable for use in most garages.
Just remember to place the dehumidifier at an ideal location, and high humidity levels in your garage wouldn’t be a problem anymore.