Condensation under mattresses

[poguelife]

This past weekend we took our brand new hybrid out for the first time. We had a bit of rain, so I was super vigilant, looking for any leaks. The tenting and seals all made out great, but I was a bit startled, because in being thorough looking for leaks, I removed the mattresses and felt wettness on the bottom of the mattress, as well as the bunk-board. This was the same on all 3 of our tip-outs. The following night, one of the kids was scared and slept with us, so no one slept in that tipout; consequently, no dampness under that mattress but condensation under the mattresses where people slept. I was spooked at first, fearing leaking, but it became quite evident that this was just condensation. The overnight low was in the low 40's so I suspect the body warm through the mattress meeting the cold air underneath the bunks =condensation.
... is this a common thing? Anyone else want to pitch in with their experience on this? The user manual talks about condensation as one might typically find it, on the tenting, but I was surprised to find it under the mattress.

[PAThwacker]

I have never had condensation under the mattress on my HTT. The pup yup, HTT no. Must have learned a few tricks over the years.
#1 Keep air moving with 12vt fans
#2 Keep roof vent and windows open
#3 PUGZ
#4 Never put reflectix under the mattress.

[gwh1bass]

BigSkyTrailer Guy wrote:
My first reaction would be to check the fit on my Depends.

Well if you wear Depends, you are not drinking any beer and sleeping in my camper!

[BigSkyTrailer_G]

My first reaction would be to check the fit on my Depends.

[vnsquire]

We always have dampness under the mattresses. Since we rarely stay in one campground for more than two nights, I just flip the mattresses when I pull them in, so the bottom can dry during the day. The flip out bases are formica-like, so I don't see (or expect) any damage to them. We haven't been camping in high humidity areas much, so that may be factor.

[poppin_fresh]

We place a sportsman blanket (foil side up) under each mattress before making the beds. They fit perfectly, keep the mattress warmer and have prevented me from ever experiencing moisture under the mattress.

After our first trip out a couple years ago I felt like the mattress was very cold and stealing body heat all night. After buying the sportsman blankets, I have never experienced a cold feeling mattress again.

[bikendan]

This is not uncommon.
if you did a search here on the topic, you'd find hundreds of posts about it, over the past years.
it generally happens when warm bodies sleep on mattresses that are on cool exposed bed platforms, especially when humidity is high.

Hypervent can work but is helluva expensive.
you should Google so you understand how it works.
there are other similar products used for marine applications.

[poguelife]

I have the "heated mattress" toppers.... but we also have very warm sleeping bags so I was wondering if anyone has experimented with putting the heated pads UNDERNEATH the mattress to keep that side warm to avoid this problem?

[poguelife]

chast wrote:
Hi--our 20+ years of full-timing and our experience with condensation led us to a product called Hypervent. It is a marine product that addresses the condensation problem. Solved the problem for us. Google "hypervent" and I hope this helps put your mind at ease.

...was your condensation problem under the mattreses? I'm not sure if moving the air around would help with this particular problem.

[RoyB]

My OFF-ROAD POPUP TENT bed is just a pull out 3/4-inch plyboard type thing. It did the same thing.

I installed the 2X2 carpet squares from Lowes under both tent beds ends which worked great keeping that from happening. We also have 3-inch magic foam on top of the mattress now as well... I personally sweat more sleeping on the magic foam toppers. I 'm one that has to have a foot sticking our all the time when sleeping.

We liked the 2X2 carpet squares so good went a ahead and put them down on the cold floors of the POPUP. Was kinda neat not to have the cold floor anymore haha. The downside however is we do alot of off-road camping and we really bring in the small leaves on our boots etc. The carpet is hard to sweep out as compared to the vinyl floor...

I have DARK GREEN carpet squares under the tent beds and DARK BLUE carpet squares on the floor.

Roy Ken

[chast]

Hi--our 20+ years of full-timing and our experience with condensation led us to a product called Hypervent. It is a marine product that addresses the condensation problem. Solved the problem for us. Google "hypervent" and I hope this helps put your mind at ease.

[SoundGuy]

poguelife wrote:
The overnight low was in the low 40's so I suspect the body warm through the mattress meeting the cold air underneath the bunks =condensation.
... is this a common thing?

I've been reading the forums for ~ 15 yrs now, BBMs before that, and I'd say yes, for many hybrid owners condensation forming on the underside of the mattresses is not uncommon. That said, we owned a TrailCruiser C21RBH that had but one hybrid bed at the front of the trailer, therefore only one hybrid platform w/tenting, and never had this problem at all, not even once. I did however always make sure the trailer was properly ventilated by keeping a few window flaps open, with a fan to keep the air moving inside the camper. I can imagine though that with 3 hybrid tip outs this could be a problem you may just have to live with.