I just bought a Trail Lite B+ 211s with 8.1 Chevy engine. This is my fifth motorhome (others range from an old 20' Vagabond, and three Winnegagos, from 19 to 32'. This vehicle is fantastic. I am...
To be exact, it's TPO membrane over a luan plywood base. What most people do with those is either just screw into the luan, or use wellnuts in the luan. With liberal use of Dicor sealant. Apparently either one will hold the panels just fine.