Do I Need A Dehumidifier in Basement? Here’s The Answer!

Many households have basements with unchecked humidity and trapped moisture. Over time, this condition will result in bigger problems like molds, funky smells, and a slew of pests. The good news is that moisture control just got easy with electric dehumidifiers. So the question is this: do I need dehumidifier in basement? When should I get one?

Regardless of your basement’s condition, dehumidifiers would be an excellent investment. It helps you keep humidity in check, especially if your area is prone to flooding. You can also use the dehumidifier in other parts of your home that need moisture control.

Should I use a dehumidifier in my basement?

If you’re wondering whether your basement needs a dehumidifier, the following conditions will help you find the answer:

1. Your basement has water damage.

Water damage due to leaks or flooding is a tell-tale sign that you need a dehumidifier in your basement. This is the only effective way to get rid of deep-seated moisture on your basement walls, floors, cabinets, and ceiling.

Take note that even though the surface looks dry, severe water damage can push moisture deeper into the material. It may take weeks for this moisture to evaporate. By that time, pests and molds have already taken over.

Once you have removed the pools of water in your basement, the next step is to run a dehumidifier. Make sure that it’s properly sized to your basement, as well as the amount of moisture you need to remove. For massive water damage, multiple units might be necessary.

2. Your basement has funny odors.

Funky and musty odors are another sign that your basement needs a dehumidifier. Such odors stem from mold growth and bacterial growth in your basement. If not addressed right away, this can spread all over your home and cause recurring respiratory issues within your family members.

Stale odors can be due to a lot of things. Since basements often lack ventilation, ambient odors may start to add up and result in an unpleasant smell.

If discolorations accompany the stale smell on the wall, your basement is probably harboring molds. A dehumidifier will deprive the mold spores of their much-needed moisture so that they won’t spread even more.

However, it’s still crucial to call for professional mold removal, especially in the worst cases. Haphazard mold removal may cause the spores to spread in other parts of your home.

3. Your basement has been unchecked for months.

Basements that have been left unchecked and uncleaned for months likely have trapped moisture. It’s important to run a dehumidifier in this condition to combat any potential mold growth.

Aside from moisture removal, cleanup is also necessary. Basements can easily harbor the nastiest pests and growth due to the dark and moist environment.

4. Your basement walls have condensation.

Another way to know if your basement needs a dehumidifier is to touch the walls. If it feels damp, it’s a sign that there’s condensation going on. You should also check the basement window (if there’s any) for any mist-like buildup that indicates the presence of high humidity.

Dampness is more common during the spring and fall seasons. This is because most homes won’t be running their HVAC systems during these periods. It will result in damp air being trapped inside the basement.

5. Your basement is infested with pests.

Are there rodents and bugs inside your basement? This means that there’s a hidden source of moisture somewhere.

Like molds, pests thrive in darkness and moisture. Unfortunately, basements often have these two elements, making them prone to a massive pest infestation.

Once you’ve taken measures to eliminate the pests, the next step is to get rid of the moisture. Again, a dehumidifier will be the easiest way to do this if you don’t want to hire a moisture removal service.

Overall, the dry air will make your basement less inviting for pests. However, you should note that moisture removal is just one of the steps you need to take to prevent pest infestations. Sealing entryways and removing food sources are also necessary.

6. Your basement has rust.

The presence of rust on metal items in your basement indicates excessive moisture. Rust forms when water or any acidic substances get in contact with metals. Over time, the metal will corrode as the iron reacts to oxygen and moisture.

So if you discover rust-covered items in your basements, you should consider running a dehumidifier right away. I also recommend using a basement air purifier to get rid of airborne irritants and nasty smells.

7. Your basement gives a clammy feeling.

Did you get a clammy or cold feeling when entering your basement? Nope, there are no ghosts. Instead, it’s the excessive humidity left trapped inside your basement.

A dehumidifier can easily fix this problem. But if the damp feeling isn’t going away, it’s best to check if there are pipe leaks that cause the unending moisture.

8. Your basement has creaky doors, floors, and windows.

Lastly, if your basement floor, doors, or windows are creaky, that means moisture has been absorbed into the joints. The moisture will cause the wood to expand, which will loosen screws, nails, and other fasteners. The result would be a creaky sound.

Take note that the creaky sound also indicates a compromised structural frame. Your window or door joints may give off soon without repairs. As for your floors, you’ll notice the wood warping and lifting from the ground.

How to set a dehumidifier in your basement

Using the dehumidifier right is crucial in optimal moisture removal in your basement. Here are a few reminders I recommend:

do I need dehumidifier in basement
Photo Credits – Sylvane
  • Place it on the floor. It’s always best to place a basement dehumidifier on the floor for practical and safety reasons. First, dehumidifiers will have better air convection circulation when placed on the floor. Aside from that, it’s safer to leave the dehumidifier running on the flat ground. This way, it won’t tip over, especially if you’re planning to leave it on overnight.
  • Keep it away from any vertical surface. Dehumidifiers should be placed at least 2 to 3 feet away from walls and any vertical surfaces. This way, the wall material won’t dry too much or too fast. When that happens, the material will crack and become damaged. Also, dehumidifiers tend to release warm air, which can be a fire hazard on flammable materials.
  • Set the right humidity target. Most dehumidifiers have built-in humidistats. This is to allow the equipment to monitor the amount of moisture it still needs to collect. When in doubt, you can also use a separate humidistat for more accurate readings. Overall, you should aim for relative humidity not higher than 55% to 60%.
  • Consider multiple units. For large basements or those with excessive humidity, using more than one dehumidifier is ideal. This is to remove the moisture faster and to prevent the unit from being overworked. You can also alternate the units for round-the-clock dehumidification.
  • Always check the water reservoir. Dehumidifiers have a water reservoir inside that you need to drain from time to time. For continuous operation, you should look for a basement dehumidifier with a continuous drain feature. This way, the collected water will be drained through a hose. It takes the need to manually remove the reservoir.

How to choose the right dehumidifier for your basement

humidifier in a room
Photo Credits – Abt Electronics

The success of moisture removal in your basement depends on the dehumidifier you’re going to use. It’s important to get the right one by considering the following aspects:


The first thing you should check is the capacity of the dehumidifier. This should be based on the size of the basement where you plan to use it.

The rule of thumb is to get a dehumidifier with a capacity of 5 liters for every 500 sq. ft. of floor area. So if you have a 1,500 sq. ft. basement, the dehumidifier capacity should be at least 15L.

You can go bigger, depending on the moisture level you’re currently dealing with. I advise getting a 22L to 30L unit for 1,500 sq. ft. basements that are heavily water-logged.

Aside from its moisture extraction capacity, you should also check the size of the water reservoir. For overnight and non-continuous drain operation, I’ll go for the largest possible water bucket. But, of course, this usually comes in high-capacity units that also cost more.


Another thing you should check is the drainage method of the dehumidifier. Most portable units have a built-in water reservoir that needs to be drained manually.

However, if you’re running the dehumidifier for long hours, you should consider getting a continuous drain. This can be found on larger units intended for massive room areas.

The dehumidifier has a hose slot with a continuous drain where the water will flow instead of going into the reservoir. However, this method requires access to a sink or outdoor area where you can let the water drain.

✔️Air filter type

Some dehumidifiers are also fitted with filters to trap large particles like dust and debris. It’s not intended to clean the air thoroughly, but it’s surely an added value to your purchase. Besides, the filter will prevent the dirt from clogging the coils and motor.

These filters are either washable or replaceable. It’s important to check this part since it could mean additional expenses on your part.

✔️Built-in humidistat

It’s also important to get a dehumidifier with a humidistat. This way, you can set a target relative humidity level to prevent drying the air too much. However, make sure that the humidistat has an accurate reading.

Overall, this feature also makes the dehumidifier cost-efficient. Most units with this feature will shut down automatically once the ideal basement humidity level is achieved.

✔️Auto defrost

Lastly, I recommend a basement dehumidifier with auto defrost feature. Sometimes, ice can build up on the coils, which will impact the rate of moisture removal.

Frequently Asked Questions

Q: Do I need a dehumidifier in the basement in winter?

A: Since the air is mostly dry during winter, running a dehumidifier in your basement may not be necessary. Also, most dehumidifiers need to operate at a temperature not lower than 60F. Otherwise, the humidity level will be too low, and there wouldn’t be enough moisture for the device to collect. Worse, the dehumidifier will make your indoor air dry and irritating.

Q: Will a dehumidifier in my basement help the entire house?

A: Even if you’re only using the dehumidifier in the basement, it will benefit your entire house. This is because the moisture in your basement will no longer spread to other parts of your home. Also, removing the excess moisture in the basement will reduce the risk of a pest infestation.

Q: How do I keep my basement dry without a dehumidifier?

A: Increasing airflow, opening windows, and placing desiccants in your basement will help lower relative humidity levels. However, this is far from the moisture removal of dehumidifiers. If your basement has high levels of moisture, you badly need to use a dehumidifier for optimal results.

Q: Where should I place a dehumidifier in my basement?

A: Putting it at the center of your basement will be ideal. This way, the portable dehumidifier can circulate the air evenly and collect as much moisture as possible. You can also place it closer to spots with bigger water damage. Overall, you should keep dehumidifiers away from walls and flammable materials.

Q: How long does it take a dehumidifier to dry a basement?

A: It would take a dehumidifier anywhere from a few days to a week to fully dry a basement. It depends on the moisture present in the room, temperature, and the capacity of the dehumidifier. If you want to speed up the results, you should use multiple dehumidifiers in your basement.

Final words

Do I need dehumidifier in basement? Most of the time, yes, you need a dehumidifier to keep excessive moisture at bay. It will also prevent mold growth as well as the proliferation of pests in your basement. Just make sure that you get the right type, capacity, and features that match your needs. It’s also crucial to pair a dehumidifier with regular cleaning to turn your crawl space and basement into habitable areas.