looks like a nice project, but as my resident mechanical engineer has instructed me, "Did you float the tiles?"
In other words, anytime you have a moving sub-surface, wood flooring, frame house on piers, bad slabs, etc., you must put a layer of plastic/visquene under the tiles.
This allows the tiles to "float" while the sub-flooring moves.
If you do not do this, regardless of how "firm" your sub-floor is, you'll have cracked tiles--even slate tiles-- in short order.
This can even happen when you have a full blown concrete slab, even though the slab does not show any signs of cracking.
Hope this helps.....
regards---rhjames
