Large Format Tile Installation

Large Format Tile Installation
Kathy Munson, Interior Designer Custom Installations, Inc.

Go into any retail store that sells tile and you will notice a trend that has been around for a while now. This trend is gaining speed and now you will notice that most popular tiles on the market are what are called “large format” tiles. That is that they measure over 15” either in length, width or both. This is causing a change in the way that tile are to be installed.
During the manufacturing process of making these larger tiles the ability to keep them all flat and true is difficult at best. Because of the variation in the tile from the manufacturing process; the way that they are installed is also more difficult.
Side view of Large format tile
As you can see with this side view of an average large format tile; the ability to keep them from bowing up in the middle of the tile is the issue. The yellow area between the straight line at the bottom and the bottom of the tile is the variation that we see with most large format tile. The difference may not even be visible to the naked eye for some people. This is what causes the issue when you set the tiles next to one another. The middle of the tile does not come at the same flatness as the outside edges.
Without proper techniques you can have an issue with “tile ledging”. That is the difference in the thickness of the tile from piece to piece or one side of the tile to the other. To combat this ledging issue there are patterns that are used to mask the differences. One of the most popular ones is to do a 1/3 stagger. See the drawing below for an example of the layout in a 1/3 stagger:
one third staggerThis stagger pattern is most commonly used with the popular wood look tile that are on the market now, but is can be used in any large format tile application to minimize ledging. The change one third down the tile keeps the tile middle from the end and therefore hides any differences in thickness. As a matter of fact if you read the tile boxes the manufacturer will recommend that this be done for this reason.
Another method is use of different techniques like using a leveling system to hold the tiles even while installing. This is often done only by a professional installer.
Proper setting materials are REQUIRED to make sure that your large format tiles are properly supported and that the setting materials will not shrink back therefore causing a bond break between the tiles and setting materials.
There are additional ways such as leveling pours to handle difficult applications of larger tile. A floor has to be flat within ¼” in 10’. That is considered a “super flat” floor…and may not even be attainable. If a larger tile is installed on a floor that does not meet this you may experience significant “lippage”. That is where one tile may stick up higher than those next to it. This can become a trip hazard if the lippage is large enough. Make sure that your application is going to work without major floor prep before choosing the tile for your project. We prefer to see a project first before giving an estimate for this reason. We look at subfloor conditions to ensure that we find the product that will work the best for your situation.
Installation of a large format tile is often thought to be something that should “cost less” because you do so much area with just one tile. However, the need to ensure proper coverage of setting materials negates this difference in size. It actually may take longer to install that a smaller tile.
Even though the larger tiles are beautiful and do make spaces look larger, they also have some definite challenges in the installation process. Hiring a competent professional to do your installation is the best way to insure that your tile project turns out the way that you expect it to.