Thanks RDThose are too general to provide the whole picture. Here in the Sonoran Desert we have many months of near zero RH BUT have a month or more of monsoon season where the RH may stay 80-100%! This fall has been the wettest I have seen in my near 20 years here with >50% for a week at a time, over and over.
Interesting “real world” experiences. Thanks for reporting your findings. You pioneers in the PM builds will be able to provide much needed data for us who follow in your footsteps ?I understand that most do not use their vans in the coldest temperatures, but as a reference, and perhaps as a starting point for discussion, I will describe our first trip in the van when it was still a bare metal box. Christmas in Wyoming, 2014, traveling at ~ minus 25°F. (Thank you, heated side mirrors.) The van heater kept us warm in the cab area, even with no curtain, but over the entire interior of the cargo area, we had a solid thick coating of rime ice. It sublimated with no evidence of passing through the liquid state.
Last year, I unexpectedly encountered rime ice at about 8°F in the channels below the rear side windows which I had not yet insulated or enclosed. Given that these areas were open to the warmth and humidity of the interior, I must assume that rime ice can form on any metal surface thus exposed, as in the van surface of any uninsulated channel. Here again, it must have sublimated, because I saw no evidence of there having been liquid water.
i recently removed my kitchen counter which sits below the window behind the driver. It had been in place for three years. Again, there was the channel that I had not insulated, but this one was isolated from the living space by the counter. Here, there is evidence of water drops in the accumulated dust on the metal “window sill”, but no harm done. There is no suggestion of moisture on the underside of the Baltic birch counter, which probably had two coats of varnish.
You are welcome, I truly think you are a thoughtful & helpful guy (Yes opinionated, but in my mind that is what we need here). Thank You RDRV8R,
Thanks for the kind comments, and yes I have opinions! I wasn’t being critical but wanted to relate the issue that going to the desert might seem like the answer but we have our moisture issues here too. You can probably drive out of RH issues but we find in reality that is not practical. For us the condensing issue is important and of course releasing our own moisture is a huge factor. For us venting all the time to get to ambient and heating when we can to lower internal van RH has worked even in S Mississippi in early summer. We cook inside but do not boil, no shower, awning windows open and vent open some at night. So far so good.
Thanks KOVDon’t cook or shower in your van unless absolutely necessary. Always keep your roof vent and a window opened enough if possible to provide air flow thru the van.
Thanks HarryNI haven't seen them widely used (possibly due to cost) but there is a device called a "low temperature dehumidifier".
A normal dehumidifier works by cooling the air (like an air conditioner) and condensing out moisture. It is intended for use in warm / hot weather and isn't effective for lower temperature use.
A "low temperature" unit is designed for conditions such as a winter in the pacific northwest. Cold, damp air - not only nearly saturated, but also carrying water as an aerosol.
It works like a freezer. The air passes over a coil that literally "freezes out" the water, then re-warms it with the waste heat. Just like in a freezer, the coil is periodically allowed to warm up and the water drains out.
Don't be fooled by the ones that work on a thermoelectric effect - not nearly as powerful as the ones that work via a compressor.
I don't own one, but have seen then for sale on the usual on-line platforms.
RnRAnother thing that I discovered is the dreaded plastic triangle subterranean cavern dilemma. A lot of people believe that this is some form of deliberate drainage system to drain away interior moisture. However, I'm certain that the holes in the bottom are for draining when the shell is dipped in the liquid rust proofing/primer. Because they are plugged afterward to prevent water from getting in. The gaps where the spot welds are, near the rear wheel well, simply have sloppy gaps and are not intended for drainage. Actually, it appears they attempt to seal them with the undercoating, but usually do a sloppy, poor job. With the rake of the van, they only allow for water to enter when flung off the rear tire (many posts on water accumulated in that area and not draining at all). I would suggest thoroughly drying and sealing this area, as once it's covered up with insulation, paneling, cabinetry, etc, it's a good place to have excessive moisture permeating up into your walls and insulation, creating condensation on cold walls and mold in insulation and wood furring strips.
And rusting screws and screw holes.