Tiling on a raised foundation

It sounds like your saying your house is off grade with a wood subfloor? If you put hardibacker on this; that is the correct way and shouldn't be causing you problems. However were your joists underneath built well enough for the weight so you don't have any deflection?

To help figure this out, go to WWW.JOHNBRIDGE.COM

They have a program in the tile forums that will help you figure this out called DEFLECTO. Then go talk to everyone there and they'll walk you through anything you need so you'll have a great floor.

We are having the same problem right now, and it was done by a licensed contractor. We had the foundation of our 1920's home "reinforced" a couple months before the new floor was installed. The grout was pretty wide because of the large, thick clay tile. The contractor is chipping the grout out and they are going to replace it with mortar to see if it helps. Fingers crossed.

I made the same mistake. Three grand later I am wishing I had just done a nice hardwood... Our solve is grout caulk.

I’m considering new waterproof interlocking laminate that will have more flexibility as the tile keeps cracking on my raised foundation. The moldings will need to be replaced as the floor will be lower.

I also had the same problem, as the areas of grout crumble (which turns out to be not all , probably more heavy traffic areas) I go back and repair with the colored sanded grout chalking. Wish I had just grouted with it in the beginning or found a wood product that can stand up to any water in the kitchen and looks nice.