RV Life Hack: Stop Moisture & Mold Growth Under RV Mattress

Why Does Moisture Collect Under An RV Mattress?

Moisture is a big issue inside RVs, travel trailers, and 5th-wheels. You can run a dehumidifier and do everything you can to keep the humidity down but most people forget about the RV mattress.

Everything else in the camper can be bone dry but you lift up your mattress to find moisture and maybe even mold growing on the mattress and the wood underneath.

Related: RV Condensation And 14 Ways To Prevent Mold In Your Trailer

Mattresses inside RVs, vans and even rooftop tents are laying on a cold surface. When you sleep on your mattress the warmth from your body heats it up.

Moisture from the air and your body start to condensate between the bottom of the warm mattress and the cold surface it’s laying on.

If not kept in check you could very quickly end up sleeping on a moldy mattress every night. It will eventually damage the wood under your mattress and could potentially threaten your health.

RV mattress moisture and mold is no small issue. But the good news is you can do things to help stop the condensation and get airflow under your RV mattress.

3 Simple Ways To Prevent Moisture & Mold Under RV Mattresses

These are some easy ways to stop moisture from building up under your RV mattress and keep mold from growing.

I say RV but these methods can be used for other common places where moisture builds under mattresses like boats, vans, skoolies, tiny homes, and rooftop tents.

1. Air Out The RV Mattress

Perhaps the most simple way to keep moisture from building up under your RV mattress is to air it out by lifting it up and placing something under it.

You can use cans, step stools, basically whatever you can find that will support the weight of the RV mattress.

See Also: Best Small RV Dehumidifiers That Help Prevent Mold

If you have a fan or dehumidifier you can place it near the mattress to suck out moisture or get air flowing. If you are camping or living in a climate with very high humidity and rain you may want to do this every day.

Be sure to keep a close eye on it, if a day of being aired out isn’t enough to get the bottom of the mattress and the wood underneath completely dry you may have to incorporate some of these other methods as well.

Place cans under the RV mattress to lift it up. Then use a fan or dehumidifier to dry.
If you don’t want to have to place something under your RV mattress to air it out getting an airflow pad like the one below is a fantastic option.

2. Insulate Under The Mattress

A budget-friendly way to prevent condensation is to use cardboard to insulate under your RV mattress. Take one or two layers of cardboard and cover the entire area under it.

This will help lessen the temperature difference between the RV mattress and the cold wood underneath.

This method is a quick easy fix that will work well in moderately humid climates. You should check the cardboard weekly to make sure there’s no moisture collecting.

You may need to replace it every year or so. Make sure you still air out under the mattress after cold rainy days.

3. Use An Under Mattress Airflow Pad

The best way to make sure no moisture ever builds up under your RV mattress and to help the airflow underneath it 24/7 is an anti-condensation ventilation mattress underlay.

Den-Dry Mattress Underlay

Den-Dry Mattress Underlay-Queen

Check Price at Amazon

The Den-Dry Mattress Underlay is made with spun polymer and plastic which makes strong weaves that can hold up an entire mattress allowing for air to flow underneath, even when you are sleeping on it.

The benefits of something like this are permanent anti-condensation and constant airflow. Even in hot humid climates moisture won’t collect and mold will have a hard time growing.

When it’s been extra wet outside just place a dehumidifier in the bedroom or point a fan towards the RV mattress to create even more airflow. You won’t have to lift up the mattress all the time to place cans underneath to elevate it.

Related: Do I Need To Run A Dehumidifier When The RV AC Is Running?

There are 3 sizes of underlay mats. There’s a twin size (click to view on Amazon) that measures 38″x74.5″ which can be used under a boat or RV bunk bed.

The queen size comes in two strips that are 39 inches by 60 inches. A camper queen is usually 60″ wide and 74-80″ long. You can cut the mat down to size to fit any length of a queen mattress.

There is also a king mattress size (click to view on Amazon) which is 2 pieces that are 39″x70″.

All of these mats are very lightweight, even the king size is only 8 lbs.

The Den-Dry Mattress Underlay is going to be the most permanent, low maintenance solution for preventing nasty mold from growing underneath your mattress.

This mat can be used in even more than just RV applications, It works well in vans, rooftop tents, boats, and any other kind of mattress or foam pad that has issues with condensation and moisture collection.

It also helps give mattresses and sleeping pads a little more spring which can make them slightly more comfortable.

Click Here To See A Full Review & Installation Instructions For The Den-Dry Mattress Underlay

Why Is Preventing Moisture Under An RV Mattress Important?

Mold is the silent killer. It can destroy almost anything in an RV, boat, van, tent, and even a home. Mold can also cause health issues, including asthma if left in your living space for too long.

I’ve seen too many videos of moldy walls being torn out of trailers and moldy RV mattresses being thrown away to ignore the importance of keeping moisture out of RVs.

See Also: How Do I Stop My Clothes From Getting Damp In An RV Closet?

If you do just one of these 3 simple things you will save yourself a lot of time and money in the long run.

What If My RV Mattress Is Already Moldy?

If you look under your RV mattress today and find that it’s covered in mold and the wood underneath has mold growing on it make sure you take it out of your RV right away.

If there are only a few spots of mold you may be able to clean it all off and save the RV mattress.

To clean a slightly moldy mattress start by vacuuming off all the loose dirt. Then clean off all the mold and mildew by using a mixture of equal parts rubbing alcohol and water. Once the mold is totally gone rinse with warm water.

Then apply a mold killer like Concrobium Mold Control Spray (click to view on Amazon) to make sure every bit of the mold gets killed and prevented.

See Also: Best Indoor & Outdoor Weather Stations For Home and RV Use

If the mattress is too far gone it’s better to throw it away and get a new one than risk more mold growth.

After taking care of the RV mattress wash the moldy wood that was underneath it. If you don’t get all the mold that’s growing on the board it will just grow back into the mattress.

If the board has become soft and damaged you may need to replace it. Be sure to spray mold killing chemicals on the wood part as well.

Make sure everything is totally dry before putting the mattress back into the RV.

Have any more ideas for preventing and getting rid of moisture under RV mattresses? Leave a comment below.

by Jenni
Jenni grew up in a small town in Idaho. With a family that loves camping, she has been towing trailers since a very young age.

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