QUESTION

I have new apartment, and the tiles in that apartment are getting debonded. The tiles are 600mm X 600mm X 10 mm UGL polished porcelain granite tiles. Upon inquiry, I came to know that they used mixture of Protland Composite Cement (PCC) and water for tile installation. All the tiles were covered from back with the bonding agent. What can be the reason for de-bonding? Your answers will be a great help. Thank you in advance.

ANSWER

ANSWER - There are many potential reasons why a tile would debond.  Generally speaking the failure is never due to a single deficiency, but rather due to several compounding deficiencies.

When you say a Portland Composite Cement, I assume that is a sand and Portland cement mixture.  This is normally used as a mortar bed to level or adjust the floor.  The bonding agent I assume is a thin-set mortar, which is typically a Portland cement and sand, with special chemicals such as polymers to increase the bond strength.

Porcelain tiles require a high bond strength thin-set mortar because porcelain tiles are impervious by definition.  The manufacturer of the thin-set should state it meets ANSI A118.4 and/or A118.15.

That said, the installer may or many not have used the correct installation adhesive.  They could have miss used the thin-set mortar and let it sit too long before embedding the tile into the thin-set, which could have skimmed over.   They may have not properly prepared the tile substrate and there may be contaminates that are acting as bond-breakers and that could cause tile debonding.   They may not have properly cleaned the back of the tile before installing it, which could have inhibited the ability of the thin-set mortar to bond to the tile.  They many have left off movement joints at the perimeter of the rooms or within the tile area, which can cause the tile to be subjected to excessive stress.  The floor that the tile is installed over could have excessive deflection, which can cause the tile to be subjected to excessive stress.

Without performing an intrusive inspection by a experienced and qualified, you can't determine what caused the tile to debond, as it is likely due to more than one of the above conditions.