Yeah never know when outside invaders want to come knocking though you are knocking on adding extra weight more than usual to the rig so I would be careful. Nothing can stop wood from rotting when you don't know you have a leak and that usually what causes all the destruction.Floor repair done same as rear areas.
Galvanized sheet metal on top of frame outriggers and rails, 1/8" plywood, 2x framing as needed, 1 1/2" foam between framing, and 1/2" plywood on top.
Lots of quality caulking below and plenty of construction adhesive within.
I used pressure treat lumber wherever I could. You never know when the rot or carpenter ants return.
Less than 50°F hehe, been tweaking on mine and its been getting down to 0°F just haven't posted any pictures lately of wiring. You must be in a warm climate area that's not usually below 60°F.More tomorrow as I work at less than 50°F.