As for my horse stable, I was wondering if I should just flush with the ground cause I know I won't cement under the shed but I wonder about rotting later on down the road. . Its gona be about 12x10, just an out the weather shed. I will paint it by the way, not sure if I will prime it first then paint later though. Might just put a coat of paint on the osb but it won't be right away anyway. Any suggestions guys?