I have a 7x16 continental cargo trailer that I am thinking about converting. I came across this forum, and wow! what a bunch of great ideas. One of the primary uses will be winter-hunting and taking my wife and three kids skiing to ski areas in the PNW. It usually doesn't get super cold around here, but would like to prepare for down to 0 or so. Obviosly we have warm sleeping bags, but it would be nice of the trailer would retain heat overnight.
So my first question is about insulation. It looks like most people have taken off the interior panels and installed 1.5" foam board R7 or so insulation between the studs. How well does that work in cold temps? Glued or taped or just hung? And did you tape the seams?
I was thinking about placing an additional layer on top of the metal frames, and just using longer screws to put the plywood back on, like a SIP. That could double the R value to about 14, and eliminate (lessen) heat transfer through the metal, at the cost of 3" of interior space. Seems worth it to me.
I also am considering foam spray particularly for the underside, but it could be used all the way around.
Another option is some type of foil backed bubble wrap (reflectex) as a layer in additon to or in loiu of one of the foam board.
Good ideas, or overkill? I guess I would rather pay for insulation than heat.
I would appreciate any thoughts or experience with winter camping in your converted cargo trailer.