Ceramic tile on top of paint?

[Walter R.]

I would like to install ceramic tile on top of my existing patio slab. The slab has a few non-structural cracks.

Over the years, the slab has been painted several times. The paint is in good condition. Can I get away with laying the tile on top of the painted slab? Will the thinset permanently adhere to the paint?

Of course, it would be better to remove the paint but it looks like a major operation: 11'x 50'. How would one go about removing several layers of paint from the concrete pad?

Thanks for any help.

[Richard J Kinch]

Uh, paint remover?

[m Ransley]

Sandblast it, even with stripper removing the paint you wont get a good bond due to dirt.

[scott21230]

If a power washer won't work, then try a sandblaster. The rough surface it will create should be really good for adhesive purposes too. Don't attempt to glue or otherwise adhere the new tiles to a painted surface. That's just plain stupid.

[Walter R.]

The local tool rental place suggested using one of their floor scrubbers. It uses a very coarse, open, plastic pad, about 1" thick and 17" round. Just wondering if these pads will really remove paint from concrete.

Anyone tried one of these scrubbers?

[m Ransley]

What you need to research is how mortar does not bond to old dirty concrete. The only proper way to do it is score the concrete with a diamond scoring tool. Porter Cable makes one, and you should be able to rent it. If you dont prep it right it wont last.

[Italian Mason]

This will not remove paint from concrete.

If the paint is in good shape you can use an exterior tile adheasive not cement (thinset,ect) based to apply the tile. you will need to determine the type of paint that is on the porch and use the adheasive the will work with this type. There is also an etching compound that you can/should apply to dull the gloss of the paint finish prior to adhearing the tile. as far as "non-structural cracks" the slab is the sturcture and it has cracks thefore they are structural cracks. any crack is a sign of the structure moving....adress this first.

Walter R. wrote: