Originally Posted by dzl_
Thank you. Follow up question, can the area behind the chair rail be insulated? (the shadowed area in the image above)
Yes, and in the case of our bus, it came with the standard "batting" insulation in the space. Same stuff that is in the ceiling and walls above the rail. It is about a 1" space. I'll have to measure it the next time I have access to the space. Right now, the bus is full of stuff and I can not measure it.