# Installing tile over Tile



## JoeMac (Jun 14, 2015)

I have thick paver style tile over concriet, started to bust up tile to get to slab and lay new tile. When busting up old tile it is severely damaging slab with deep pits. The old tile is stuck very well, I want to lay new tile over the old pavers. I have sanded the glaze off and am happy with that, the problem I have is that the existing pavers have some pretty severe cupping at corners. Question is do I do a scratch coat the spead the floor with a notched and then butter the back of the tile to get me over the cupping. Any help, suggestions, or advice would be appreciated. I have lots of experience laying tile floors, showers and counters I just have never layed tile over tile and the cupping issue is concerning


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## mikeswoods (Oct 11, 2008)

Unless the cupping is extremely bad, you should not need to skim coat the old tile--you are there and a pro(right?) so you make that call---use a two part modified thin set like Kerabond and Keralastic---if the concrete base is getting torn up by the demo--you might have discovered an old mud set floor--and it is the soft deck mud pulling apart.

Please go to the introduction section here and introduce yourself and your business--


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## JoeMac (Jun 14, 2015)

The cupping is pretty severe.


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## KAP (Feb 19, 2011)

Your finished tile longevity is only as good as its substrate...


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## MIKE ANTONETTI (Jul 17, 2012)

How bout a picture? Your descriptions are vague(thick pavers, pulling up slab, severe cupping) for evaluation, and "your" perception.


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## ccoffer (Jan 30, 2005)

It's pretty standard for properly installed tile to take the finish coat off when removed. I'd roll with it and then use a crap ton of thinset going back.


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## woodfloor (Oct 12, 2015)

Remove any moldy or loose grout with a rotary tool or carbide scraper. Vacuum the *tiles* and clean with detergent and water to remove dirt, sealers and wax. Rinse the surface with clear water and let it dry. Buy a latex-modified thin-set and mix it in small batches to keep it from skinning *over*.


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## charimon (Nov 24, 2008)

Grind it flat and go.


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## TNTRenovate (Aug 19, 2010)

Little EcoPrime Grip


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## Evan1968 (Dec 5, 2010)

JoeMac said:


> I have lots of experience laying tile floors


 Just a bit skeptical on that one. :blink:
Forget for a second you are going over tile. What if the concrete floor was cupped or uneven as the tile is? What would you do? 
Answer is level or flatten the floor first. How do you do that? A experienced tile setter would know how.


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