i have a similar cage, and kishi has the same problem, ony she does it on the bottom corner of her cage, i bought a roll of painter's dropcloth, it's plastic, and you can cut off what you need, i just rinse it off when she pees and alternate it with another peice while it dries,it's done fairly well with keeping chin pee off of my hardwood floors.,if you're worried about them chewing on the plastic, to can cusion it with grass mats or fleece, i use grass mats or cardboard in kishi's cage,since she chews on anything she can get her little teeth on.