Is this for a boarding facility? Honestly, Slightly graded Concrete slab with the Gutter is as good as it gets for cleaning just hose down and go, put the PVC pipe beds in (they have a sling type webbing for the dog to lay on). Dirt floor is too hard to keep up with and encourages fleas. Be sure they have an ample place to get out of the rain, heat and cold as well so perhaps an indoor/outdoor run.