This is known as reflective cracking and it can be easily prevented by adding a crack isolation membrane during installation.
How to keep floor tiles from cracking.
But the brittle nature of tiles and the constant foot traffic means that the tiles are likely to crack at some point.
Crack isolation membranes allow for slight shifts or movement of the floor that lies underneath the tile allowing it to move independently without moving and cracking the tiles above it.
Even the hardest tile will crack if a wood framed subfloor deflects too much under load.
However cracks wider than 1 8 inch will eventually transfer to the tile it notes.
How to prevent cracked tile.
In many cases the crack is not the result of an inferior tile.
Cracked tiles on floors and walls is a problem because it can be difficult to track down the source of the crack.
This could include a framed floor that has too much bounce or improper isolation of the tile from the subfloor whatever that subfloor may be.
However there are steps you can take mitigate tile cracking.
Reinforcing your floor will make for a more solid and level surface while repairing tiles with epoxy is an easy fix for single tiles that become cracked.
Generally hairline cracks in the concrete will not present an issue to the tile floor above.
In far more instances the crack was caused by anomalies under or around the tile.
Cracked tile is usually a sign of poor preparation of the substrate.
Take these precautions to prevent tile cracking in the future.
This will prevent formation of cracks in the concrete which lead to reflective.