Hi Everyone,
One thing I've noticed living in the northeast/midatlantic region is that the humidity gets to my trailer. Part of it is the humidity from my breathing, but a big part is the weather. We've had a record amount of rain this May. My trailer is 1-1/4" sandwich construction: 1/4 ply outside, 3/4 styrofoam insulation around a 1x3 wooden skeleton, and 1/4" cedar planks on the inside. The surface wood on the interior absorbs moisture from the atmosphere and expands, but the exterior plywood just underneath the aluminum skin does not. It's protected from the humidity by the aluminum on one side and styrofoam insulation on the other. The problem is that after a month or two, the ceiling and the back door become concave (looking at them from the outside, or convex from the inside). The top and bottom of the door pooch out from the seals along the door jamb, which can let in water. The ceiling arches inward so the top of the trailer can hold 1/2 inch deep pool of water around the fantastic fan! Luckily the fan is waterproofed so no water pours in. Anyone else have this issue?
The solution I've found is pretty simple. Stick a 1200 watt space heater in it for a couple of days, with the windows slightly open and the vent cap in the ceiling slightly open. The warm air inside the trailer absorbs water out of the wood (because as air warms, its relative humidity goes down, creating a differential that makes the water in the wood want to equalize by diffusing into the cabin air). The the warm air rises out of the vent taking the water with it, and pulls in cooler air with lower water content through the windows. Within a couple of days, the door and the ceiling and my bed slats all return to their normal shapes and sizes and the trailer is happy again for a few more months.
I suppose a dehumidifier machine would work just as well, and maybe use less electricity than a 1200W space heater on high, but I don't have one. I just thought I'd share what I've learned! I've dehumidified the trailer this way 3 or 4 times in the last year and a half.