Ceramic tile Installation requirements

I was going to show how a ceramic tile repair this but upon inspection of the floor there was more than meets the eye.
Support of the subfloor itself has to be sturdy no mater what kind of underlayment you are going to use.
Well in this case the underlayment was 1/2" (inch) plywood but that was not the problem.
The problem was 2"x8" floor joist where used to build the room extension. That will not be stable enough to keep a ceramic or porcelain tile floor from cracking or the grout for that matter.
A sturdy foundation is needed.
There are alternatives to this problem. Either extra support in the floor joist, one rule I tend to stand by, is if the floor joist are anything less than 2x10's added support or other flooring alternatives are suggested.
So before your heart gets set on a new tile floor, check to see what you are standing on.