[Motor31]

Unless there has been a significant change DRV uses fiberglass batting for insulation in their units. That is a fine insulation in a horizontal application. It is a terrible idea in a vertical application due to the effect of gravity. When you add in the vibration and bumps of the road the fiberglass insulation will fall. I have seen the effect in non mobile homes as well as in my own DRV unit.

The sun on the wall near where the interior temperature sensor tells the tale. I set the bedroom AC temp at night. When the sun comes up I have to turn the temp up in the summertime as the sensor gets the heat transfer from the outside wall solar heating effect. Much the same kind of situation when the wonderful folks at DRV decided the proper place to put a temperature sensor was less than 8 inches above a wall lamp. Turn the light on and the AC unit goes into a frenzy trying to cool off the sensor. Do it in the wintertime and the heat will never come on. The only insulation in the wall is now about half way up from the floor. When I pulled the window on the side wall of the slide I saw there was no insulation there in the wall at all. Just a nice 1.5 inch open air dead space. That was on the deep slide next to my chair.

You might want to reconsider the foam insulation issue. It is not fiberglass batting that folks who manufacture freezers, refrigerators or even ice chests use to insulate their products. Foam will not fall from where it's placed like fiberglass batting when used vertically. It dies not compress from the effects of gravity even in a horizontal application like fiberglass matting does.

Lastly no 5th wheel trailer will be comfortable in SD / ND winter weather without setting it up properly. That means skirting and using a heat source in the basement plumbing area and possibly in the propane tank area as well.