> The floor surface is 3/4" plywood.
> The main purpose of the shed is for storing motorcycles,
I also built a shed with 3/4" plywood floor, that I hoped to use for
storage of motorcycles. When the weather turned cool in the fall, I
found moisture condensing on the underside of metal surfaces, so I moved
the bike back to my concrete floored garage. The bike was covered with a
light weight breathable canvas cover. I haven't noticed condensation
problems with my lawnmower or other stuff in the shed (which I don't
worry about as much as on the bike.)
My point of all this is, you may want to consider some time of moisture
barrier if the shed is just plywood over dirt.