I am laying tile on a cement floor which in the basement. The room is approx. 12x18 and is the furnace room. The floor had been painted by the previous owner. Quite some time ago we decided to add a fresh coat of paint but the new paint never adhered all that well. It pealed and flaked until it is a real mess. We are thinking about laying down tile but are concerned that the glue may not adhere well. The tile is commercial grade and not the peel and stick variety. Do we need to be concerned about the adhesive: please don't say scrape all the paint off!.
Answer:
Scrubbing it with a cleaner and steel wool will help prepare the surface. A concrete paint primer on top of that would tell you a lot. If after a few weeks it doesn't appear to be peeling, particularly in traffic areas, I'd try putting down the adhesive and tile. If that doesn't work, your worst fears have just been realized - a flat scraper is best but you have to be patient.