Loose floor tiles and slab foundation issues
Houston engineering home inspectors are essentially unanimous: floor tiles that pop loose are rarely, if ever, caused by foundation movement.
Foundation movement, even foundation movement that is well within a normal, expected range, can crack floor tile.
But it is virtually impossible for foundation movement to cause well-bonded floor tile to pop loose. Floor tile is bonded to the slab surface with what is called thin-set. This material does an excellent job of bonding the tile to the slab surface if it is applied properly. The key is for the slab surface to be clean and free of any contaminants. The underside of the tile must be clean but this is usually not hard to achieve. The slab surface is another matter.
It is easy, during normal construction to get materials on the slab surface that will prevent a good, permanent bond.
When this is the case, the tile may eventually come loose.
In summary, this problem is almost always a bonding issue and not a foundation movement issue.