Collins Chair Rail Recommendations
My 2003 Collins has what seems like the standard chair rail made out of something similar to unistrut. It is riveted to the side wall. The panel below the rail is one with the floor and side walls (or is welded to them at a minimum) - there's no real way to get behind it without cutting a hole in it. The upper panel is fixed with the same rivets that hold the chair rail on the bottom, but regular Torx screws on the top.
The question comes as to what to do with the upper panel as far as insulation. I was originally going to remove it and put board insulation in its place. However, it's only a 1" cavity behind it, I can't insulate behind the lower panel (and so will have to insulate in front of it), and the chair rail seems beefy enough that as many people say, it may be helping the wall structure to a degree.
Does it make sense to remove the chair rail and upper panel so I can better insulate? If the rail is best left in place, how about running some sheet metal shears near the bottom? On the flip side, I'm now thinking it may just be best to leave the panels in place and just put 1" foam board over them. I'm not living in the bus, just taking vacations in it, and don't plan to be in extreme cold (but possibly high heat).