Everything's better when wet

[BigT]

It's the condensation that occurs when the warmth and moisture exuded from a sleeping body meets the cold be it an air mattress, a piece of plywood or the concrete floor without having a way to dissipate.


In warm temperatures the underside of the bed remains within range of the sleeping body and no condensation is formed. When the impermeable layer meets with moisture at the right temperature (which varies), then it gets wet.

So does that mean I'm going to have issues with this design?  
Foam glued to plywood, covered with indoor/outdoor carpet, spaced off the floor by legs.  I don't have any holes drilled in the plywood, but there's no reason why I couldn't add some if needed.  

Living in the Bay Area we seldom get really cold or wet weather, but it does happen once in a while.  

 

[WriterMs]

Two thoughts....

I don't know how "waterproof" indoor/outdoor carpeting is (or if it is "breathable"). If fairly waterproof, it might be the same sort of thing as having a plastic cover on like RVPopeye. The moisture collects on his sleeping bag but he can then just keep that aired out. So a big question is.. at what layer does the moisture collect?

The second thing is that even if it is not a problem in Bay area temps, are you not planning to venture out to other climates now and then?

 

[907KHAM687]

I didn't have any ice on the metal skin last night. I think I was just to close to the ceiling with the bed as high as it was.

I bought a waterproof cover when I ordered the mattress and I finally put it on last night. Woke up this morning warm and clammy. I think that foam was drinking up a lot of sweat.

I think the ultimate solution will be to drive the van somewhere warmer.

Hank

 

[907KHAM687]

So does that mean I'm going to have issues with this design?  
Foam glued to plywood, covered with indoor/outdoor carpet, spaced off the floor by legs.  I don't have any holes drilled in the plywood, but there's no reason why I couldn't add some if needed.  

Living in the Bay Area we seldom get really cold or wet weather, but it does happen once in a while.  

I think your going to have issues. If the carpet isn't waterproof your going to end up in my situation. Or worse, I could inspect under my foam, and after a month and a half in a relatively cold climate I had a black cloud. I don't even want to think about what a year would have looked like. If the carpet is waterproof odds are moisture is still going to get in somehow and be trapped.

 

[surfer]

Get a "buddy board", the kind used on bunk beds.  I posted a pic last year of what it looks like. It allows the mattress to breathe. If the moisture has no place to escape it will just build up till you have the mold back.

Slats work just as well.  Someone mentioned IKEA as a source for bed slat system.

Good luck.

Did you mean to say Bunky Boards? I didn't see anything relevant under buddy board. If you did mean Bunky Boards hear's an ehow:
http://www.ehow.com/how_5103896_make-bunkie-board.html

 

[flying kurbmaster]

are you guys sure it is not an issue with holding moisture in the van, from other sources like the buddy heaters, or propane stoves without an extractor on. I don't have any problems with moisture under my beds in any of my vans, I sleep on 2 inch high density foam, with sheets on them, a sheet of plywood with no holes, In very cold weather I get a tiny bit of condensation in the morning when heater has been off, on the ceiling in one of my cupboards despite drilling holes in the sides to move air around, the van is insulated with a vented propane heater , an extractor fan over my propane stove, I don't have an issue with condensation and nothing under the bed, no moisture at all, so that is why I am wondering if there is more to this story another source\ reason for the moisture build up.

 

[SternWake]

The condensation will be attracted to the cold plywood platform. It is the aluminum 32 degree beer can in 98.6 85% humidity, and your mattress is a thin squished porous foam cooler.

It happens even in mild climates, it just happens more, the colder the bed platform is, and when the human sleeping on top has more blankets keeping the body's respiration next to the mattress for longer.

BigT, A weekend here or there is not going to have issues with your set up. Every night, then, problems.

Sit it out in the sun after a weekend. YOu could use a holesaw carefully, and place some holes strategically so as to not weaken the plywood too much.

I love draping my mattress over a sawhorse on a warm dry day in direct sunlight, well actually I hate the effort required, I love the result.

 

[Almost There]

So does that mean I'm going to have issues with this design?  
Foam glued to plywood, covered with indoor/outdoor carpet, spaced off the floor by legs.  I don't have any holes drilled in the plywood, but there's no reason why I couldn't add some if needed.  

Living in the Bay Area we seldom get really cold or wet weather, but it does happen once in a while.  

Maybe, maybe not!

First because you're living in a temperate climate, so you're not as likely to see the temperature/moisture combination that causes condensation.

Secondly, because the underside of the plywood is open to the air, the temperature under the bed is going to be more likely to be comparable to the ambient temp of the van. The only condensation will be directly caused by the amount of moisture that your body discharges through the night AND the ambient temperature in the van.

Condensation occurs when warm moist air meets colder temperatures. The specific temperature at which this occurs is on a sliding scale depending on humidity levels relative to the temperature so it's impossible to say that it will occur when the temp in the van gets to XX degrees.

IIWM, I'd be drilling some holes in the plywood bottom to allow the mattress to breathe and allow moisture to escape. Even 1/2" holes every couple of inches in a laid out pattern will help. You don't need to do them around the outside 6 or 8" because that's not where you're going to have the core of your body laying while you're sleeping.

We get in trouble in the vans because of solid wood platforms and enclosed spaces beneath them such that the air under the bed gets cold and our body heat warms the foam mattress. Of course keeping the underside of the bed wide open means that we have no storage space under there so that's not a good solution.

I got in trouble once in my apartment because I had my foam mattress salvaged from a van directly on the floor. The floor was carpet directly over concrete. Worked fine until winter hit and then I went to move the mattress to install the platform bed my ex finally got around to building me. The carpet and the underside of the foam were soaking wet.

 

[compassrose]

You guys have missed it. The problem is the MEMORY FOAM. Every memory foam topper that I have used has moisture problems. I live in a dry desert and still had the moisture problems until I solved it. It is a problem inherent in the memory foam. If you read reviews for pretty much any memory foam product you will see people complaining about them being "hot" in the summer. You need the memory foam to be able to either evaporate the moisture (like your body sweat) or prevent it from absorbing it in the first place. That is the goal. Now you can either spend a lot of money or a little bit of money to fix the problem. Your choice. Just keep in mind, if you go the expensive pad under the memory foam way, you need to replace that foam every two years. The body sweat seems to break down the foam structure.

 

[Almost There]

You guys have missed it. The problem is the MEMORY FOAM. Every memory foam topper that I have used has moisture problems. I live in a dry desert and still had the moisture problems until I solved it. It is a problem inherent in the memory foam. If you read reviews for pretty much any memory foam product you will see people complaining about them being "hot" in the summer. You need the memory foam to be able to either evaporate the moisture (like your body sweat) or prevent it from absorbing it in the first place. That is the goal. Now you can either spend a lot of money or a little bit of money to fix the problem. Your choice. Just keep in mind, if you go the expensive pad under the memory foam way, you need to replace that foam every two years. The body sweat seems to break down the foam structure.

I have to disagree but I've had condensation problems in two separate scenarios, neither of which involved memory foam at all, one didn't even include foam of any kind.

The example I gave in post #28 involved old upholstery foam from before memory foam was even available. It was laid directly on top of carpet over concrete. Major wet spot (and no I didn't wet the bed... ) on the underside of the foam and the carpet in the dead of an Ontario winter.

The other time I've had condensation problems in bedding was when sleeping in my ripstop (breathable fabric) hammock with a ripstop underquilt and then a silnylon (non breathable and water resistant material) as an outside layer to protect my backside from the wind and the cold. When the temperatures dropped to 32F the second night, I stayed dry and warm but there was a puddle in the silnylon underquilt protector in the morning from the condensation that was created by my warm body and the cold air meeting at a point where the moisture was trapped.

Memory foam may be particularly vulnerable to condensation issues because of its' composition but it is not the cause of condensation issues.

 

[compassrose]

I have to disagree but I've had condensation problems in two separate scenarios, neither of which involved memory foam at all, one didn't even include foam of any kind....

Memory foam may be particularly vulnerable to condensation issues because of its' composition but it is not the cause of condensation issues.

Same solution though.

 

[compassrose]

Ordered a twin memory foam mattress off amazon

And this is why I addressed the memory foam problem.

 

[TravelDerby]

I wonder how an under layer of this vinyl lattice would work?  It would probably give a bit of air flow, won't rot and is pretty cheap.

http://www.homedepot.com/p/Veranda-...l-159-in-x-47-5-in-x-95-in-73004026/100011154