If you are having tile installed on a second floor, make sure they qualify that your floor doesn't flex too much for tiles to set properly. The subcontractor told us that ours flexed too much after it was installed. My tiles now \""crunch\"" as I walk on them. They were kind enough to extend the warranty to two years, but I was told by the subs this would happen, so it does no good to complain. Just be aware.