Laying tile on top of tile (Flooring)
Ceramic can be set over existing ceramic using unmodified thinset mixed with liquid latex---
Kerabond and Keralastic by Mepei is a good example.
The existing ceramic must be perfect---Scuff the old tile with course sandpaper first--An angle grinder with 36 grit paper (two disks back to back) makes for a quick scuff.
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