Had carpet in bathroom for a while, that is until the cat, for whatever reason, turned the bathroom into his own personal litter box. We pulled the carpet and put down tile. No mold or anything else under it, just having to seal where the cat did his thing. That being said, no carpet in bathroom. But I do wonder how people with hardwood floors manage. What would be worse is SCHOOLS with hardwood floors in bathrooms. (shudder)