Compared to sensitive floor types like hardwood or laminate floors, tile floors are a lot more resistant against urine. The floor won’t be ruined so long as you clean up the mess quickly. However, if urine is left for several hours on tile floors, it could ruin the grout. The best defense against this is to seal up the grout, as well. Sealing the grout won’t just protect against urine, but also discoloration caused by dirt, dust, and other things.