Problem is that paint acts as a bond breaker. So putting thinset cement on top of the paint will result in the cement bond being broken by the paint.

Most tile companies will physically remove the paint by abrasion. Chemical paint strippers will appear to have removed the paint, but it will be liquefied and then have the chance to sink down inside the surface of the concrete, possibly prohibiting any bond to anything in the future.
ciciliotandson

Thank you both for your responses. I was afraid that we would have to sand off the paint if we wanted to use tile. Bummer.

Another question, then. What about engineered hardwood floors? We thought about doing a glue down hardwood. Would that work over the painted concrete or are we going to have the same issue?

Problem is that paint acts as a bond breaker. So putting thinset cement on top of the paint will result in the cement bond being broken by the paint.

It doesn't actually break the bond. The thinset bonds to the paint, but then the installer can't guarantee what kind of bond the paint has to the concrete below it. Too many times people have tiled over painted concrete, only to find out the paint really wasn't bonded well, and as a result the whole floor came right back up on them, even though it looked and felt like the paint had a good grip on the slab.

As for gluedown hardwood, you're right back in the same predicament. Anything to be attached to the floor by means of adhesive of ANY kind, you're going to have the same problem.

Thanks Bill. I'm afraid that we're going to end up just taking a chance because I really don't want to do a laminate floor and I don't know what other options we have at this point.

No, you cannot glue down wood to painted concrete. The paint is the bond breaker.

Thanks for the feedback. We have begun the process of scraping up all of the paint. I'm hoping this works because I really want tile and refuse to do any laminate flooring.

Jenny, if you can get up 80% of the paint, you should be good. You don't need to remove every single trace. But I'm glad you decided to go this route, as much of a PITA as it is. I think you'll be happier in the long run.

Thanks Bill. It's been a lot of work for my husband and our contractor but I know that I will be happier in the end. BTW, we picked a wood-look tile for the wet bar area and I can't wait! I'll have to come back with pictures when it's finished.

have you considered that dricore product? Or perhaps a layer of XPS covered with wood?

My bathroom floor was painted now the paint is coming of piece by piece..

They put on a sealant (its black in colour) on concrete first then they painted..

Is it possible to scrape the paint of and then tile the floor..

Waiting for your reply..

Thank you Sue von Ruben.