The steel which covers the insulation in the interior side walls, does this need to go back after I reinsulate? I was going to run 1/4" plywood up the side walls but I'm not sure if that would be structurally the same.
Bruce
Those panels are part of the structure.
Yes the panels are structural. You will have to decide for yourself what you are going to do about it. I left the panels off and added bracing in each section and then used ½ plywood. I'm not an engineer and not sure if I got enough strength from this but haven't had any problems. The bus as a motor home is used and loaded differently than when it was for hire. If you are worried about keeping these panels and saving the original structural integrity then you will want to put back with structural rivets.
Each His Own
John
Let me add my two cents here. We never put those panels back in our conversion. Sure, they very well may be structural, but since we were skinning the interior with 3/4" knotty pine, it really wasn't an issue. I'm not saying this flippantly and I wouldn't encourage you to disregard some of the older wiser gents here, but I had to just add my experience. If you're skinning with wood, your coach will be plenty strong. Many times, when they are converted, our coaches end up a little stronger than they were when we started and yet they won't be working as hard since they won't be filled with passengers and luggage. Our coach is lightweight in the 32,000 lb range. We did cross brace in the spaces where the windows used to be, but not down below...
You can tell if they are structural or not by how they are attached. In my bus I am pretty sure they are fairly light aluminium pop riveted on. That is not structural. If they are riveted every inch or two with large rivets that retain the inner pin or are solid bucked rivets (like the roof and the outer skins) then the panels are structural. I think they can be removed without much penalty to strength.
Brian
They are held on with structural rivets 3/16" I think(they have the center pin that has to be punched out before you can drill the heads off). I replaced the panels before installing my interior walls, but I only used paneling on the walls. With the thin panels I have on the walls, I like having the aluminum back there because they hold screws well.