I'm about to start my floor/bottom and before I make my first cut I thought I'd ask if anyone has ever used two pieces of plywood 4'X8' and 1'X8' rather than two pieces 4'X5' (actually 48"X59" since I'll have an insulated wall with the 1/2" exterior plywood sitting on the trailer frame).
I got some nice looking/reasonably priced 1/2" paint grade maple plywood that will be the floor. I plan to seal it with CPES and probably cover that with polyurethane or some other finish.
I plan on building a sandwich floor using a 2"X2" frame under the 1/2" ply and 2"X4" under the plywood joint. I might even seal the joint with fiberglass before I seal everything with asphalt emulsion, insulation ans 1/4" plywood for the "roadside".