tiles over tiles
Ceramic tile can be installed over the top of existing ceramic--IF-the original tile is sound and properly installed. (some times it's not--cracks,loose grout--all indicate failure)
The old tiles need to be cleaned of all dirt,oils and wax--roughed up a bit if shiny--a grinder with 60 grit sand paper is handy.
Use a two part thinset --powder and liquid latex--Kerabond and Keralastic by Mapei is a good example of a two part thinset.----Mike---
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