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82tpsmith's avatar
82tpsmith
Explorer
Dec 24, 2013

Cold weather condensation in tough spot...

Well this is our first season in the 5th wheel in freezing temperatures and it has been fun, but a bit challenging. Already had the 10' poop-cycle, freezing water lines, frozen fridge and all the joys of shoveling :)

I've gotten all that fixed thanks to a lot of great posts on here. But here's the most recent one.

At night, and all day I guess, I've noticed when I put my hand in between our mattress and the slide out wall there is ice build up, even frozen to the wall. I ignored this for a little while, yesterday I decided to put the pink foam-board in between the wall and mattress. i think that will keep the moisture off the mattress. Today I took the cover of our mattress and noticed a bit of mold on the part of the cover that sits below the mattress. So i then looked at the wood that mattress sits on and it is very noticeably wet and moldy. Now it's not from a water leak as it is really only in the middle of the wood frame and not the sides. My guess is that since the slide out bottom is not insulated that the super cold air is condensating to the inside wooden bed frame?? I don't know. Anyone else have problems like this. I'm afraid I'll have to replace the wood, but I just want to try and make sure it doesn't keep doing this?
Seeking Advice

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  • sowego's avatar
    sowego
    Explorer
    Dec 24, 2013
    From what I've learned nearly all RV aren't insulated well enough to endure extreme cold.

    It is typical for there to be condensation on the outside wall at the end of the bed and forming ice on the window frame (if you have one).

    When we wintered in our MH this indeed did happen. Lets face it with humans breathing and exhaling warm moist air the cold walls will indeed do this.

    Our fix was to pull the mattress away from the wall a couple of inches so air could get in there. We tried to keep the window frames dryer by opening the blinds daily and drying off the windows, frames and even the walls. A couple of spacer made from small rolled up towels can help you achieve that or just find any object, like an empty butter dish or two.

    If your overall interior humidity is too damp try using a dehumidifier.

    Luckily the space under our bed platform (that raises up) was not damaged with moisture. You might try insulating this area to help prevent future problems or installing vents in the bed base to allow air to flow in there to allow temps to equalize.

    Good luck...indeed winter RVing is a challenge.
  • 82tpsmith's avatar
    82tpsmith
    Explorer
    Dec 24, 2013
    westend wrote:
    You'll need to raise the mattress so it gets some ventilation on the cold surface. Keep the mattress away from the wall or add a thermal break from the wall to the mattress (a piece of 1/4" foam sheet comes to mind).

    If it was me, I'd make a new mattress platform with 3/4" space between the new platform and the existing platform. In between the 3/4" ledgers that support the new platform, I'd install 1/2" extruded foam board with foil backing. The 1/4" difference will allow for an airspace so that there is ventilation to the original platform, averting rot, hopefully.


    I like this idea. i too thought if I could get some air in there that might keep the condensation down. I did add some of the foam board around the mattress to keep it from runing the matress, but still worry if the walls might get the mold and dampness that it is showing now.
  • 82tpsmith's avatar
    82tpsmith
    Explorer
    Dec 24, 2013
    well I dug a little deeper and took up the plywood platform that the bed lays on to see what I might be dealing with, not good.

    view of slide out with plywood base for bed removed


    Close up of some of the mold


    another


    Well, as you can see, not good. I had just replaced the plywood platform about 2 months ago too. It was sagging in the middle from the weight of us sleeping. None of this mold was on that slide out board. So not sure what to do. I'm a bit worried it is up in the walls too.

    Can I just paint some "KILZ" paint on top to seal it in? Does the whole slide out need to be replaced? Will insurance cover something like that? Needless to say the DW is a bit concerned, as am I. I've done a lot of repairs, mods and what have you to our rig, but this one gets me a bit nervous.
  • 2oldman's avatar
    2oldman
    Explorer II
    Dec 24, 2013
    camperpaul wrote:
    Another of the miultitude of reasons my rig does not have any slide-outs.
    That's probably as helpful as telling him to move to a warmer climate.
  • camperpaul's avatar
    camperpaul
    Explorer
    Dec 24, 2013
    Another of the miultitude of reasons my rig does not have any slide-outs.
  • newman_fulltime's avatar
    newman_fulltime
    Explorer II
    Dec 24, 2013
    When you shower open a vent or window to draw moisture out get a fan moving air will keep it dry
  • westend's avatar
    westend
    Explorer
    Dec 24, 2013
    You'll need to raise the mattress so it gets some ventilation on the cold surface. Keep the mattress away from the wall or add a thermal break from the wall to the mattress (a piece of 1/4" foam sheet comes to mind).

    If it was me, I'd make a new mattress platform with 3/4" space between the new platform and the existing platform. In between the 3/4" ledgers that support the new platform, I'd install 1/2" extruded foam board with foil backing. The 1/4" difference will allow for an airspace so that there is ventilation to the original platform, averting rot, hopefully.
  • poncho62's avatar
    poncho62
    Explorer
    Dec 24, 2013
    Your everyday RV is not insulated well enough to use in the winter....some are better than others.

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