Prevent Mold With An Under Your House Dehumidifier
If you have moisture problems coming from under your house you need to get on top of it now before it causes more expensive issues later on and a dehumidifier for crawl spaces will help you remove unwanted dampness and odors.
The prevention of mold growth in the crawlspace is a simple process when you have an under house dehumidifier. The most common cause of mold and mildew is excessive humidity, which can often be resolved by increasing ventilation.
Homeowners who suffer from hard water, pest infestations, mold, and mildew problems have discovered an excellent way to combat these issues. It’s called installing a dehumidifier under your house, and it’s surprisingly easy to do.
If you live in a house and have any moisture problems, it can be hard to remove, but with the right dehumidifiers for the house, it is not impossible.
Can I Use A Regular Dehumidifier In A Crawl Space?
A crawl space is a difficult place for a dehumidifier because airflow in and out is limited. This means that if you tried to install a regular, portable dehumidifier in your crawl space that the dehumidifier would draw moisture out of the air in your crawl space and into itself.
Those two things aren’t good for each other! Dehumidifiers are designed to take moisture out of the air, and they need to breathe so they can do that. But in a crawl space, there’s no way for the moisture to escape!
While many have used larger (50 pints plus) “normal” dehumidifiers with some success you are best using a dehumidifier specifically designed for crawl spaces such as the ALORAIR dehumidifier which is the most powerful dehumidifier available.
This is indeed the best crawl space dehumidifier on the market and really is quiet as a mouse, so to speak. It is a great addition to your house, it also can be used for industrial applications, business, or commercial use as well.
AlorAir Commercial Crawlspace Dehumidifier
The AlorAir dehumidifier is a very expensive dehumidifier however it stands head and shoulders above the rest for performance in removing moisture from under your house, in your crawl space, basements, or any other large area.
AlorAir Basement/Crawlspace Dehumidifiers come with an air intake ventilator plug-in that pulls stale air from the inside of the home while pushing fresh air from outside to dehumidify under your home.
AlorAir BAS245BAS Basement/Crawlspace Dehumidifier is an ideal solution to control mold and mildew caused by excess moisture in your basement, crawl space, or other enclosed areas.
AlorAir Basement/Crawlspace Dehumidifiers 198PPD (Saturation), 90 Pints (AHAM), 5 Years Warranty
AlorAir uses technology that has been proven environmentally friendly to control the humidity level of the air in your home. It does not rely on refrigeration coils, drain fields, or any other energy-consuming features. It is designed specifically for homes with basements/crawl spaces where moisture and mold are a concern.
AlorAir dehumidifiers work in below-grade spaces to remove excess moisture and prevent the formation of mold and mildew. Equipped with a number of features to reduce the hassle caused by excess humidity, AlorAir dehumidifiers are the efficient, easy-to-use solution you’ve been searching for.
What Customers Who Use This Dehumidifier Under Their House Said About The AlorAir Crawlspace Dehumidifier:
Took A 1400 Square Foot Crawl Space From 70% Humidity To 45% In 24 Hours. Great Product!
It’s been almost 2 months since I installed this and it’s still running strong. It took my crawl space from 80% humidity down to 35% in in just a few days. I’m running the drain hose about 10′ with a 4′ vertical climb and the pump is working great.
Best Dehumidifier…
- It’s been raining for days here. But even with the crawl space vents open the humidity level in the space dropped from above 75% to about 60%. Since I blocked the vents yesterday, it’s down to 50% and dropping.
Crawl Space Use, Set To 55 In 2nd Season – Flawless Operation…
- Did a lot of research, and settled on the AlorAir due to its good, and the RJ-45 connected remote display which I have mounted in an easy-to-see location in the house. In 2nd season and working flawlessly – very quiet, can’t hear it
Plus, It Cycles On And Off, Runs As Needed…
- We purchased this dehumidifier to remove excess moisture from our crawl space. It’s doing a wonderful job. Previously we were running 3 smaller units and they were running constantly. Our new unit, Model HDI90, brought the RH down to 38, which we never could previously.
This Dehumidifier Is Doing A Great Job…
- The dehumidifier seems to be doing a great job so far. 2000 sq ft crawl space with sealed vents and it’s keeping it just below 50% humidity.
This Is A Commercial-Grade Product…
- Not a big box store sale item. It actually does what is supposed to do. I have a crawl space and live about 300’ from the beach so the humidity is high. The crawl space is set for 40% humidity. The product delivers expected results.
It Can Be Set And Left Alone Under The House To Manage Itself…
- It definitely removed water at a good pace. Installed it in the crawl space under the house. Sealed all vents and the humidity went from 98% to 70% just from this one device (the house is 2200 sq ft). Running for 3 months now no issue – That’s with the wet ground which is next to be covered to help the unit get us down to 55-60%.
Great Dehumidifier…
- Did much research for crawl space dehumidifier for 1800 sq ft crawlspace. initial humidity level 66 – 68%. After installation, dropped to 63 – 65%. Contacted AlorAir on Facebook. They were quick to respond and offered great advice on sealing crawlspace from the outside air. They continued their follow-ups until I was able to reach 52 – 54%.
I Love It When You Power-up New Equipment And They Just Work…
- I’m using this dehumidifier in my crawl space. I started by laying down a 10 mil vapor barrier and after firing up this machine, the humidity level went from 54% to 38% in just a couple of days. The internal drain pump is what sold me. All I had to do is drill a hole in my PVC drainpipe end cap. Squeezed in the thick vinyl drain hose making a super tight fit. Plugged in the remote control and turned it on – DONE!.
No Longer Have A Moisture Problem…
- After going through two standard dehumidifiers in the last 3 years I decided to spend the money on a good one for my crawl space. This was easy to install (after leveling the dirt/stone floor). I attached a garden hose temporarily and started it up. It lowered the humidity level within minutes.
Great Solution To Humidity In Your Crawl Space…
- Had water dripping off my ductwork. Very humid and was worried about mold and fungus. Installed the Alorair and within a few days, the water was gone. Sealed up my vents, replaced the vapor barrier, and installed an Alorair HD 90. Relative Humidity went from the high 90s to below 50% within a week. Highly recommended. Easy to install.
AlorAir Crawl Space Dehumidifier
This is the smaller and cheaper version (still expensive) of our top-ranked dehumidifier for under the house and just like its bigger brother, it has plenty of happy customers using it to great effect in their crawl space areas.
AlorAir Basement/Crawl Space Dehumidifiers Removal 120 PPD (Saturation) 55 PPD (AHAM)
What Customers Who Use This Dehumidifier Under Their House Said About The AlorAir Basement Dehumidifiers:
It Ran For 2 Months Straight Day And Night And Never Once Had A Problem With It!
Have been waiting until all the water was out of our crawl space to do this . It took this machine two months and it did an amazing job. We had a lot of water and this guy was pulling 10 gallons in 24 hours. We are super pleased with how well it worked. Don’t hesitate, just buy it with confidence.
Smell And Miserable Humidity Is Basically Gone On Crawl Space Over A Single Weekend…
- I installed Friday evening in a crawl space (about 1400 sq ft) that was at 99% humidity at 76 degrees. By Monday morning the humidity sensor I put in said 55% at 77 degrees. This thing has been trucking along and the drain is constantly running so I’m happy for now.
It Works…
- I set it up, turned it on, and it worked. The crawlspace humidity is down in the 40s today. When I installed it we had droplets of water collecting on the mind ductwork and the insulation on the branch ductwork was soaked in some areas. There were puddles on the plastic covering the floor of the crawl space. Humidity was in the 80 percent relative humidity range at the start.
This Is A ‘Set It And Forget It’ Product…
- Just finished encapsulating my crawl and set this up as the last item to complete the project. Also purchased a remote control unit. It drains smoothly and you don’t have to worry that sagging will cause issues. I ran it continuously for the first 24 hours and it brought the space from 67% to 48%. We had thunderstorms this weekend and the unit quietly kept the space at about 55% for the entire time.
House Is Now Cool, Comfortable, And Dry, And A/C Runs A Lot, Less…
- This dehumidifier worked WONDERS in our wet crawlspace within hours! Humidity has been very high (70-80%) this summer and made the house smell musty and damp. Water was collecting in pools on the crawlspace plastic floor cover. After just HOURS of being set up, it was pulling gallons of water out of crawlspace air!
Using As A Crawl Space Dehumidifier…
- Had 80%+ humidity in my crawl space – after about a week of running, now the humidity is down below 50%, and the dehumidifier cycles on and off. The fan blows strong enough and directional enough to circulate the air too.
Cost-Effective Solution To Crawl Space Humidity…
- It really dried out my basement crawl space easily from over 65 % to 43%.
Better Than A Regular Dehumidifier…
- Great for controlling humidity under the house. Works wonders and has a remote monitor available. Pretty quiet.
Aprilaire 1820 Pro Dehumidifier
This is another very powerful under-the-house dehumidifier that performs extremely well. You may need to get this one professional installed for you unless you really know what you’re doing.
Clean, fresh air is a house’s best defense against mold, mildew, and unpleasant odors. The Aprilaire 1820 Pro water dehumidifier helps reduce the humidity in your home up to 50%, carrying out moisture from the air in your basement and the surrounding areas.
The Aprilaire 1820 Pro Whole House Dehumidifier is the ultimate dehumidifier for the largest, dampest areas. With its durable polyethylene tank and high-impact polymer support legs, it’s built to last.
Aprilaire 1820 Pro Dehumidifier, 70 Pint Commercial Dehumidifier for Crawl Spaces, Basements, Whole Homes up to 2,800 sq. ft.
The Aprilaire Model 1820 Pro is the top-of-the-line dehumidifier and ideal for older homes with little or poor ventilation, where humidity levels often run high.
Humidity trapped in walls and attics can lead to mold and mildew, and dramatically shorten the life of building materials next to foundations such as wood decks and vinyl siding.
This dehumidifier is one of the most popular on the market because it is very reliable and protects your home from mold and mildew.
Aprilaire Model 1820 Pro dehumidifier is a reliable, energy-efficient way to control mold and mildew, wood rot, odors, and other moisture problems in your basement.
What Customers Who Use This Dehumidifier Under Their House Said About The Aprilaire Pro Dehumidifier:
The Aprilaire Reduced The Humidity In My 1,380 Square Feet Crawl Space From 92% To 48% In 48 Hours!
I placed it in my crawl space, attached the external condensate pump, plugged it in and turned it on. For convenience, I have it placed near the crawl space door pointed towards the middle of the crawl space. My crawl space is 36” high. I can’t hear the dehumidifier running from inside the house.
Spend The Money, You Won’t Regret It…
- In our new home, we have a half basement and half crawl space. Both regularly have humidity levels near 60% and mold had started to grow in the crawl space area. Once the unit gets your space dried out, it shuts down. It then samples the air and if it deems it necessary, only then does the dehumidifier kick in.
Worth Every Penny…
- Our crawl space was basically dripping water from humidity and this dried it up. Try this before you spend the money encapsulating your crawl space. Our whole home feels cooler and we can tell the difference in the air quality and the whole crawl space is dry. This system does not disappoint!!
Dehumidifier For Crawl Space…
- Got a house near the water, crawl space was 89% humidity, installed this, and within an hour was at 50%, wow what a difference.
If You’re Needing To Get Rid Of Humidity In An Attic, Basement, Crawl, Or Your Whole House This Is What You’ll Want To Do It…
- We purchased it to go into our crawlspace, which is quite large. It’s not fully encapsulated but it is sealed off and new poly has been put down. In a matter of 3 days, it went from 93% humidity to 55%. It is built like a tank, VERY quiet (especially if you use insulated ducting, which we used to push the dehumidified air to the other side of the crawlspace).
Reduces The Risk Of More Mold In The Crawl Space…
- This is installed easily into our crawl space and doesn’t require a drain. After going down to the crawl space a few days later, it is clearly a lot less humid. We expect this to lower our A/C bill, to extend the life of our heat/air unit also located in the crawl space.
The Aprilaire Dehumidifier Is Very Effective…
- My Dehumidifier broke and the humidity under the house was 61. I got a price of $4000 to replace it. I bought the Aprilaire from Amazon for just over $1200, $425 to have it installed. Today my Humidity under the home is 44.2. Great product with a 5-year warranty!
hOmeLabs 4,500 Sq. Ft Energy Star Dehumidifier
The hOmelabs dehumidifier also has a lot of comments from people successfully using it under their houses with great effect and is much more affordable. As one er phrased said… It pulls moisture out like a champ!
The hOmelabs 4,500 Sq. Ft Energy Star Dehumidifier is a way to combat high humidity throughout your entire home. This dehumidifier is designed with a built-in drainage system and energy-saver setting to ensure optimal indoor comfort throughout the whole year.
Damp, musty air can come from many sources – your basement or crawlspace, a hot attic, or your laundry room. Regardless of what causes it, mold and mildew thrive in it. Remove dampness with the hOmeLabs 4500 Sq. Ft Energy Star Dehumidifier – the largest capacity unit in its class.
hOmeLabs 4,500 Sq. Ft Energy Star Dehumidifier for Extra Large Rooms and Basements
Moisture in the air can cause issues that you don’t even notice – until it is too late. But now, you can eliminate moisture, odors, and other things you hate with our portable dehumidifier. Using an automatic pump-free compressor to convert water into an odorless, tasteless liquid gives you the comfort you deserve.
The hOmeLabs 4,500 sq ft Energy Star Portable Dehumidifier is just what you need to eliminate moisture from the air at home, work, or wherever you don’t want it. It even eliminates unpleasant odors so you maintain a clean, fresh environment.
With its built-in fan, ventilation, humidity sensors, and display readings, this digital dehumidifier is an ideal addition to any room in your home.
What Customers Who Use This Dehumidifier Under Their House Said About The hOmeLabs Dehumidifier:
This Thing Is Beast! Got My Crawl Space Down To 40% Humidity!
Working great in our crawl space under 1544 sq ft damp area and keeping it dry Removed moisture under house.
Dropped The Humidity In My Crawl Space By 20 Points…
- I installed this unit in the crawl space under my house. The humidity was running in the low to mid 70’s and it smelled musty under the house.
Use This In My Crawl Space Under The House…
- Works great at a fraction of the cost of the dehumidifiers sold for crawl space use. It keeps the humidity +/- 2% of the humidity setting on the unit. I keep it at 50-55% all year
Great Product…
- The space under our house had a lot of humidity and water dripped off the a/c vents. We bought this dehumidifier and have been very satisfied with it. It is keeping the humidity level at 50%.
Helped To Remove Moisture From Our Storage Area…
- Very easy to set up. I used it to take the humidity out of the storage area under the house.
Helps Manage Basement Moisture…
- We do not empty the holding tank by hand, we have it in our crawl space which is elevated about 4′ above the main basement floor. and it’s hooked up so the condensation drips into a pump tank that periodically evacuates the condensate to the septic system. It was easy enough to hook up a standard garden hose which we cut off at about six or seven feet.
We Had Trouble With The Old One Icing Up But This One Has An Auto Defrost Feature…
- Bought this for our 14×34 block wall basement with an additional 24×24 crawl space after a dehumidifier we had for 20 years quit. This is much lighter, takes up 1/2 space, is much quieter, and seems to do a very adequate job.
This Dehumidifier Is Very Efficient…
- I am very pleased with this product. Our basement is part crawl space and partly finished space with 1100 sq feet combined. It is doing a very good job of maintaining the preset humidity, even during a very hot and humid stretch of weather.
Easily Maintains An Appropriate Moisture Level In My Crawl Space…
- It is a round brick cellar with a brick floor and is open to the crawl space under the rest of the house. After running this unit from August to mid-October (a relatively dry period), the cellar has never been so dry. Could not be more satisfied with this product.
Performs Extremely Well in My Crawl Space…
- I have had this dehumidifier in my crawl space for approximately six weeks and it has reduced the overall moisture rating from 12% to 10 or less in some areas. I am very pleased and look forward to having this dehumidifier for a very long time.
Pulls Moisture Like A Champ…
- I bought two of these. The first one is installed with a hose in a crawl space that was remediated for mold and needs to stay dry for the warranty to be valid. Wow! Does this thing pull moisture!!
Keystone 35 Pint Dehumidifier
The Keystone Dehumidifier has provided a lot of help for homeowners who have suffered from leaks and moisture problems terminating from their crawl space area.
The Keystone 35 Pint Dehumidifier is a powerful, 5.0 pint per day dehumidifier that can be installed in basements or crawl spaces to remove the dampness and mold commonly found there. The 35-pint dehumidifier has an internal pump to easily drain away from the condensed water to where it belongs, outside.
The Keystone 35 Pint Dehumidifier is equipped with a digital control panel and electronic temperature control, easily set to the desired humidity level in your home.
Keystone 35 Pint Dehumidifier with Electronic Controls
The Keystone 35 Pint Dehumidifier is a whole-house solution for those looking for convenient and reliable dehumidification for their home. It is ideal for basements, cinderblock, concrete, tile or hardwood floors, and crawl spaces.
The 35-pint Keystone dehumidifier effectively controls the humidity in medium to large rooms and efficient operation will save you money. With a continuous drain option for use in the basement, crawl space, or other low-water areas.
What Customers Who Use This Dehumidifier Under Their House Said About The Keystone 35 Pint Dehumidifier:
Perfect Humidifier For My Crawl Space Where Moisture Was Causing A Problem!
I seriously needed this dehumidifier in my home. There was a musty odor and mildew formed on some furniture and walls. The problem was discovered to be that I needed a moisture barrier in my crawl space. Until I can afford to get that done, this humidifier corrects the problem.
Best I Have EVER Tried…
- I bought one and tested it out. I then bought two more!! I have one in a large stand-alone workshop/garage that suffered from very high summer humidity levels. One in the crawl space and another at my summer cottage that is closed up most of the time. These units are really quite good and are very quiet as well.
Great Dehumidifier…
- Works great. We have used it in our home after a leak and in our crawl space.
Does What It’s Supposed To Do…
- I have it in my crawl space in my house. I used a cheap hose to run the water outside. It works as advertised. Keeps the crawl space dry. Fairly quiet.
My House Smells Fresh And Clean Now With This Keystone Dehumidifier…
- Easy install, quiet, and works well removing moisture from crawl space.
Our Wooden Floors No Longer Have Damp Marks Around The Edges…
- We have had moisture problems for years. Our house is 1200 sq ft, and this guy is amazing. We can not afford the fix we need under the house, but the dehumidifier has eliminated all our inside moisture.
Moisture Under Your House Is A Serious Issue
Lots of people are concerned about moisture under their house, but what they don’t realize is that it’s the vapor in the air that will do the damage. Water has to be able to evaporate in order for it to work its way into your crawl space and house.
Your biggest worry when it comes to moisture under the house is not the water itself, but the effect it can have on your home. Water can cause the rotting of floors, walls, and wood structures. It can also lead to mold and mildew which have serious health impacts.
Moisture under the house can cause energy loss by trapping cold air in your crawlspace and attic. All of these problems will quickly add up to thousands of dollars in damages if they aren’t fixed right away.
Water vapor can wreak havoc on your home. All water contains hydrogen and oxygen, and as it moves through building materials it breaks down the wood fibers with the help of microorganisms. This leads to mold, rot, and structural damage.
And it doesn’t stop there–water vapor also acts as a ticket for pests to enter your home. It’s the moisture they want, not necessarily humidity in the air, so you might not see any condensation or mold outside your house yet still have a huge problem indoors.
Understanding this concept is important because it means you can deal with it without having to throw up your hands and call in an expensive excavation crew just to dry out the dirt – or break a sweat for weeks caulking windows and doors.
10 Things To Look For In A Dehumidifier For Under Your House
You already know you need a dehumidifier to keep your house dry and free of mold. But what should you look for in a dehumidifier?
If you’re going to use it under your house, you need the best basement and crawlspace dehumidifiers. Here are 10 things to look for that will help you make a wise decision.
1. How Much Does It Weigh?
Weight is important if you’re buying a dehumidifier for under or on top of a house. If it’s too heavy, it’ll be hard to move around or get in place. On the other hand, if it’s too light, it won’t stay in place and may even blow away from its original position.
2. How Much Moisture Can It Remove?
The amount of moisture a dehumidifier can remove depends on how much water vapor is in the air but look for one with a high capacity.
Some dehumidifiers can remove up to 90 pints of moisture per day while others can only remove 30 pints per day. The higher the number, the more expensive and larger the unit will be that is why it is important to find one that fits and that will do the job well.
3. What Size Area Will It Cover?
Get a larger unit if the area where you’ll be using it is large or has multiple rooms. One with a wide coverage area will work faster and longer than one that has to work harder because it’s working in too small an area.
4. Is It Energy-Efficient?
This term is almost meaningless as it has become so overused these days. For example, if you were to use an air conditioner to cool your crawl space, it would remove moisture from the air too. That certainly makes it energy-efficient at removing moisture but not very efficient at anything else.
5. Does It Have Automatic Shut-Off
A humidistat detects the relative humidity of the air and turns off the unit when the desired level is reached. It’s better than having to remember to turn it off yourself.
6. Does It Have A Continuous Drainage Option
If you need to drain continuously, look for a unit that offers this option. Otherwise, you’ll have to empty the bucket every day or two depending on how damp it is underneath your house and how much moisture the dehumidifier can remove per day.
7. How Much Noise Does It Make?
Dehumidifiers are noisy appliances, so if you’re looking for something quiet, you’re out of luck. However, some models are louder than others, and if you don’t want the constant noise in your house, shop around. Dehumidifiers that come with a “quiet mode” are often worth the extra money because they’ll run quieter than other models.
8. Is The Bucket Big Enough?
You want to find a dehumidifier that has a bucket large enough for your needs, whether it’s for your crawl space or the whole house. A big bucket means fewer trips to empty it and less time spent emptying it. Many of these come with a hose attachment that hooks up directly to a drain so you don’t have to manually empty the bucket yourself. This is ideal for crawl spaces that have drains but no access walkways.
9. Does The Product Have Wheels Or A Handle To Make Moving Easier?
It’s always better to find a product with wheels or handles so that moving becomes easier. You don’t want to have to carry anything heavy when moving furniture because lifting weights can be dangerous and damaging to your health over time so make sure there are wheels or handles before buying anything heavy like this type of product!
10. Will It Work As A Fan Only?
Some models come with this option, which means they can circulate air when the humidity is low without actually removing moisture from the air. This feature is usually only available on larger models and not on portable ones, though there are exceptions to this rule (the Keystone 40-Pint Dehumidifier is one).
In summary, if you have moisture problems under your house it can lead to all sorts of long-term issues with your home that will be very expensive to get fixed so you are better off biting the bullet and investing in an adequate dehumidifier to dry out the moisture as soon as possible.
The dehumidifier you need will depend upon how severe the moisture problem is, how large a space you need to control, and so forth.
By far the most impressive (commercial grade) dehumidifiers for under your house is the AlorAir Basement/Crawlspace Dehumidifiers 198PPD and if you have a smaller space the smaller version offered by the same company… AlorAir Basement/Crawl Space Dehumidifiers Removal 120 PPD
The best common household dehumidifier that couldn’t possibly match its commercial cousins but handles the issue fairly well at a much more affordable price is the… hOmeLabs 4,500 Sq. Ft Energy Star Dehumidifier
You may also be interested in… 8 Reasons Why MIDEA Dehumidifier Is The Solution For Your Home

Allan Wilson who in the offline world has an extensive background working in research, analyzing statistics, improving work processes, team leading, and implementing training to improve results and now thanks to more than 3 years dedicated to this site is now also a highly regarded researcher of brands.
Allan has a long history of developing brands online way back before blogging existed creating websites using HTML code in Notepad. Allan established brands in the Info Product Marketing arena such as infoproductmarketing, ebookresellerkit, reprintrightsmarketing, along with many other successful websites (and a few failures along the way). Allan has also authored numerous ebooks, owned and operated membership sites, created eLearning courses, and more.