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Tips to Prevent Moisture and Mold in Your RV

If you've traveled in your rig for an extended amount of time, you know moisture can definitely be an issue. It's especially an issue in very humid areas as well as during winter when it's cold outside and warm inside (hello water-drenched windows, ugh!). We've got a few tips that might help with your moisture issue, all have been tested and have definitely helped.


This is probably the easiest and cheapest option to help combat moisture issues in your rig. DampRid is basically a dehumidifier that doesn't require electricity. It's an all-natural way to remove excess moisture in the air, therefore, it helps prevent mold and mildew. The crystals absorb excess moisture and gradually dissolve into a liquid brine (a saltwater solution). Buy lots of them and put them everywhere! Also, be sure to keep an eye on them as the water levels in them can get high, and if you are mobile they can spill over. We put some of ours that could tip over in storage areas when we are mobile. Be sure not to pour the water down your drain. It's sticky water with residue from the crystals that get absorbed and can possibly clog your tanks. Pro-tip, purchase six of the buckets and then purchase a bag of the crystals to refill them. You can usually find them at your local hardware store or you can purchase them on Amazon


The size of your rig will depend on how big of a dehumidifier you need to purchase. A small dehumidifier for 150 sq.ft. is perfect for most rigs under 35 feet. We purchased this one from Amazon and we only emptied it about once a month. The only downside to this type of dehumidifier is that it is powered by electricity. If you boondock a lot, it may not be the best option for you but can certainly help when you are plugged in. 

Moisture Barrier Under Your Mattress

This is the best tip to help prevent mold under your mattress. The issue with an RV mattress is there is nowhere for moisture to go between your mattress and the wooden platform. Air and moisture can get stuck and cause major mold issues. Not a pretty sight when you turn that mattress over and realize you've been sleeping with mold growing underneath it. This seems to be a very common issue and through lots of research we discovered the Hypervent Aire-Flow Moisture Barrier. It was a game-changer! It's not terribly expensive, for a standard RV Queen it runs around $90.00. It is sold by the linear foot, so you have to find out how much you need but even adding pieces of it under your mattress will help raise the mattress off of the platform so air can flow freely through. This is a great video that helped us determine it was the best option for us. 

Other helpful tips

  • Try not to place objects close to the outside walls. Most of the inside storage areas in an RV are in the dark, so mold can grow quickly if moisture is trapped up against the walls. If you're very mobile, just try to check your interior walls in storage areas regularly and wipe them down. 
  • Wipe the inside area of your windows (especially the metal frames) often. This is a popular place for mold to grow but if it is wiped often you can help prevent it. 
  • Open interior storage areas often so they can breathe, this will also be a good time to check for items that might be touching the walls. 
  • For motorhomes, if you are parked for longer than a week and cover your front windows be sure to remove the coverings often. Moisture can get trapped in the cabin area and have nowhere to go, removing the coverings and wiping the windows and cabin area can help prevent mold growth. 
  • Run your exhaust fan in your bathroom (if you have one) every time you take a shower or even when it's a really humid day. 

These are just some of the tips we used to help prevent mold growth in our rig. What are some other tips you have to help combat moisture in your rig?

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  • Begoña


    This is a very helpful hint. Many of us starting to roam around know litle about moisture inside the RV, specially under your mattress! Keep healthy everyone!

    BWadmin on 05/24/2020 10 a.m. moderator  

    Unfortunately, it's not usually something you realize until you see it. Glad you found the post helpful. :)
  • Trekkers


    To keep moisture from our boat during winter storage we place an open plastic washbasin full of kitty litter in it before putting the boattop on for the cold season. Kitty litter seems to keep the moisture down.

    BWadmin on 05/24/2020 10 a.m. moderator  

    That's a great idea! Thank you for sharing!
  • ebendana


    We have used kitty litter, and also a regular cheap bag of charcoal...just put down a extra large garbage bag so you don't make a mess, then slice open a couple of dollar store bags of charcoal....when you get back to the rig, you can still use the charcoal for fires... Also, dollar stores sell a knock off brand of damp rid for $1.00 each


    Dollar Tree? Dollar General? Family Dollar? I don't think I have ever seen them at Dollar Tree, but I have never really looked, either.


    Dollar Tree? Dollar General? Family Dollar? I don't think I have ever seen them at Dollar Tree, but I have never really looked, either.
  • TheDeadEndUrbanFarmer


    I never woulda guessed until it was too late. Cheers, Looking into this now...

    BWadmin on 06/20/2020 10:51 a.m. moderator  

    Usually that's how you learn, the hard way. Glad you found this helpful. :)
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