February 10th, 2012

This is part of an ongoing series to help educate both consumers and trade professionals with real answers to every day challenges in the tile industry.

Q: Several years ago I had a porcelain tile floor installed. About a year later, I noticed the tiles in the middle of the room starting to buckle. What is wrong with this tile?

A: To answer this question properly we must address a couple of issues. Porcelain tiles are made within a set of industry standards. They must meet specifications on water absorption, modulus of rupture and their resistance to thermal shock, scratching, crazing, chemicals and frost. They are also rated to help you determine how slippery they are both wet and dry. Porcelain tile is a very dense product that has very little movement.

Since porcelain tile is rigid, it must be installed on a properly prepared sub-floor. The floor itself must be very level, with no deflection. To prepare the floor properly you may have to install layers of plywood, cement backer board, crack isolation membranes or some form of Portland/sand mortar or self-leveling cement mix. Also critical to a successful install is using a latex-modified thinset as the bonding agent. Simply put, if your sub-floor moves and the tile does not, the weakest point in this case, the adhesive or bonding agent will release, causing a buckling or rippling effect.

Additionally, if the floor is being installed over a large expanse, you may need to install expansion joints and be aware how tightly the tiles are being installed up to the edge of the wall. If the tile butts too tightly against the walls, the natural movement of structures can create pressure that lifts the tiles.

These are the two most likely scenarios, but there could be other factors in your tile installation failure. The Tile Council of North America sets the industry standard for installation practices. Each year, they release a comprehensive handbook detailing installation procedures. Please consult their web site for more information or call your Lexco Tile & Stone oncall sales rep to discuss your project.