It leaves a little black on the little ones rear ends but it does wash off or brush off.

For those asking, we tap on our rubber roofing floor and it does not tear up. We built a floating floor underneath with 2 by 4s and plywood.

For the person who has the grey roofing, where did you find they grey?

Its cheaper to buy the rubber roofing from a company who sells roofing materials to builders than to buy at Home Depot or Lowes.