My husband and I own a campground and want to do some improvements in the laundry room and bathrooms. It's a cement base floor with some sort of sprayed on coating (possibly vinyl?) The building was constructed in the 70's if that helps to identify the floor. We want to tile the floors. Will we have to try to scrape up the coating - not an easy task, I'm sure. Or can we just tile directly over the coating.
from the limited knowledge i have gathered in the past if the surface isn't porus enough for water to soak into it in a short time then the thinset will not stick to it either. usually you would have to remove the coating and then lightly grind the surface so the thinset will adhere. i am sure other more knowledge people will reply.
You really need to know what the coating is. There are products like Mapei Eco Prime Grip that can prime over stuff like epoxy and tile right over it. But if it's something with a silicone base you could be in for a lot of work removing it.