Marble Tile over a Slate Slab

Q: Can I lay marble tile on a slate slab that is fairly flat?
Rick
A: You can install marble tile over a slate slab, but you will need to use an uncoupling product. Gene D., one of the guys here at iFLOOR.com that works with very large commercial jobs, suggested using the uncoupling products made by Ditra of Unimat. He specifically suggested Schluter®-DITRA. After that, just make sure you follow all instruction guidelines from the manufacturer and you should be ok. Good luck!
By request from a few co-workers, I’m going to put a brief summary here as to why you want to use an uncoupling product.
When using an uncoupling layer between a solid surface, such as slate or concrete, and the tile surface to be laid. This process has actually been done for thousands of years. The uncoupling layer neutralizes the differential movement stresses between the substrate and the tile. The rib structure of the uncoupling product allows for in-plane movement, which is why it neutralizes differential movement. These stresses when neutralized prevent what cause a majority of cracking and delamination in the tile surface.