I had my 5th wheel into comox valley rv in Courtney bc for a repair job under an insurance claim. They did a terrible job. had to pay for another inspection. the insurance company tried to say that si...
I remember using 5/8" T & G plywood to replace the floor in my last TT a while back. I have never seen 9/16" thick plywood nor OSB. However, 1/2" sheathing for flooring is a little thin assuming your joist support is @ 16" on centre. IMHO