RV Mildew Mattress Problem Solved with HyperVent Marine

Do you live in a small RV with a memory foam mattress? Have you ever looked underneath the mattress?

If you’ve never lifted up your memory foam mattress, you might want to do so. Just be prepared for a soggy, mildewy mess.

RV Mattress mildew

Mildewy Memory Foam Muck

Last Fall we wanted to replace the original mattress that came with our 24′ Arctic Fox fifth wheel. But our bedroom is so small, the only way to do so was to order one that arrives rolled up, which only memory foam can do.

While researching how to replace a mattress inside a small RV, we learned that when small RVs are built, the mattress is already inside when the roof is put on and the rig is sealed up, making a mattress replacement difficult. Is that crazy or what?

So we purchased a new $450 memory foam mattress made specifically for RVs. The mattress was really comfortable but just one month into using it we discovered a gross mildewy mess growing underneath the mattress and on the bed platform, which was becoming warped.

RV Mattrress Memory Foam Mildew

We called the manufacturer to say “What the heck?” They tried to be helpful but they told us we might have a leak somewhere, or that we installed a wet mattress. They were completely unaware of the fact that when a foam mattress is installed in a teeny bedroom, condensation creates mildew underneath the RV mattress.

You see, memory foam doesn’t breathe the way traditional mattresses do, and condensation gets trapped between the mattress and the bed plank. Why a manufacturer couldn’t figure this out was beyond me.

HyperVent to the Rescue

After spraying bleach on the mildew and drying the surface thoroughly, we began talking to fellow RVers about our mildew issue. Unfortunately only a few who also live in small rigs have encountered the same problem. Of those who have, they presented what we considered unworkable solutions to help the mattress breathe; from drilling holes in the wood plank to lifting the mattress up each morning with 2′ x 4′ boards.

Finally a fellow Escapees member introduced us to HyperVent, a great solution for RV mattress mildew muck:


Had we just searched online for “marine bedding” we would have learned that the marine industry already has this problem figured out, as solutions like HyperVent have been used by boaters for years.

Prevent Mildew Under Memory Foam RV Mattress with Hypervent

How HyperVent Prevents Foam Mattress Mildew

According to the manufacturer of Hypervent:

“HyperVent is a special material that consists of a white spun polymer woven into a large open configuration that is bonded to a breathable white fabric layer. This light mesh of polymer does not compress, allowing an open layer of air to form. It is 3/4″ thick, allowing plenty of dry air to circulate.”

Prevent Mildew Under Memory Foam RV Mattress with Hypervent

HyperVent comes in 39″ wide rolls, so we had to measure our bed platform carefully for a good fit. When HyperVent is set down, the edges must be overlapped to give complete ventilation. HyperVent prevents dampness and accompanying annoyances in three ways:

  1. Allows warm air to circulate under the mattress, thereby minimizing an essential condition for condensation.
  2. The circulating air allowed by HyperVent promotes evaporation of moisture.
  3. HyperVent separates the bedding from any moisture that might form.”

Finally! HyperVent gave us the answer to our RV mattress mildew problem. We just have to be careful to lift the blankets off the edges of the bed when humitidy is high, to allow air circulation between mattress and platform.

Prevent Mildew Under Memory Foam RV Mattress with Hypervent

The total cost of HyperVent for our short queen bed was $142 with shipping: a small price to pay for getting rid of this annoying, icky problem.

This is yet another example of the value of talking to other RVers. Even if you have the most obscure dilemma with your rig, eventually you’ll find another RVer who has experienced the same problem and found a solution for it.

16 thoughts on “RV Mildew Mattress Problem Solved with HyperVent Marine”

  1. Great information! That’s a really wonderful article that I personally appreciate. I have already bookmarked it. Thanks a lot for your valuable post!

  2. Wow, thank goodness I ran across your post of how to prevent mildew/mold under a foam mattress in our RV. Where did you find a foam mattress for that fantastic price? One more thing is it hard to get the original box springs & mattress. We have not looked at that yet.

    • Sally, we found the mattress online from a company in Colorado who’s name I cannot remember. Our bed did not have box springs, the mattress sits on a hollow platform that serves as extra storage. Good luck in your search!

  3. small world sometimes…We were looking for a product like this for our motorhome and came across HyperVent..Then we found your article later.. HA!
    Hope all is well, We posted your article link on Barthmobile..

    Mike and Cindi W


  4. Mattress Insider has this product currently for $9.99 per linear foot which is cheaper than Hpervent also if you look up Mattressinsder.com Discount coupons there is a coupon for an extra 5% off your order.

  5. What is the material that is over the top of your Hyper Vent? That gray finish material. I am have the silver bubble wrap already under my mattress but I was thinking of adding the Hyper Vent, however I’m worried that it will be too abrasive on the bubble wrap I’m not having any luck finding anybody who’s had any experience with this configuration. Please let me know what you think.

    • Joe, the grey lining is part of the Hyper vent. That “silver bubble wrap” is going to defeat the purpose, since it will not allow any air flow between the mattress and the Hypervent—which is designed to “breathe” and prevent mildew from forming.

  6. How has your Hypervent setup performed for the last 3 years? Any more signs of mold? My husband and I are having a bed delivered today and just made the lovely discovery of mold starting to grow on the underside. It’s been on the ground for the past 1.5 years with no issues but my husband has been sweating a lot more at night now for some reason and I think that’s the culprit. Unfortunately, our beautiful new bed being delivered is a simple platform bed with no box spring or slats, so your solution could potentially be perfect!

    • Jess, the Hypervent was definitely the answer. We never had a mildew problem after that. Truly is a genius product. Try spraying the mattress with some light bleach/water solution and it should get rid of the mildew. You’ll just have to air it out on a sunny, warm and dry day.

  7. Thanks so much for the information! I would have never guessed what the issue was had I not read this article. I just called Mattress Insider and got my “moisture blocker” for $140, free shipping by FedEx and 50% off if I send a picture back after installation. Now that’s pretty good .

  8. Thanks for posting this! It was so helpful. My wife and I had a similar issue with mold under our mattress and we couldn’t for the life of us figure out what the heck was causing the problem.

    We’re in Colorado where it’s pretty dry and we also use a dehumidifier in our fifth wheel. The mattress company even shipped out a replacement mattress but we had the same issue with the replacement as well.

    We did some reading online and came across your post and I’m so glad we did. What I’ve learned is in a house, the mattress sits on a boxspring or on slats which provides adequate air circulation for your mattress. However, in an RV, it lays on plywood which has zero air circulation. Moisture builds but it has no way to escape which results in mildew or mold under the mattress.

    I ended up purchasing the same material you mentioned from a company called MattressInsider.com based here in Colorado. They just recently started carrying it. I did call Hypervent first but they wanted to charge me $12 per linear foot + shipping + tax. MattressInsider.com was able to cut it to fit my RV mattress at no charge and shipping was free. I can’t remember what I paid but it was quite a bit less than what Hypervent quoted.


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