“…The Large Format Tile (LFT) and Surface Prep exam was one of the first tests on the committee’s wish list due to the popularity and ever-growing size of ceramic tile found in the marketplace today. A further reason for including this test was that many times inappropriate materials are used to “fix” the floor or wall surface deviations.

Although neither the TCNA Handbook nor the ANSI Specifications actually define large-format tile, it is generally understood in the tile industry to be one with any side greater than 15 inches.  The previously mentioned popularity of these tiles is now seeing products 48 x 48 inches — and even larger. Now that we understand what is considered to be large-format tile, the proper installation standards need to be applied and evaluated.

The substrate (floor surface) supplied in this test is purposely constructed to be out of flat, meaning it has low spots that need to be corrected. The installer must determine the location and severity of these problem areas and place the appropriate trowel-applied floor patch to remedy the deficiency. Solving the floor out of flat issues could also be addressed with the use of a self-leveling underlayment. However, the committee determined that the trowel-applied patch was more appropriate since it requires the installer to utilize multiple skills to flatten the floor surface…”

To read more about ACT Large Format Tiles click the link below:

“ACT Large Format Tile and Surface Prep”

Tile Magazine
January 7, 2014
By: Scott Carothers

http://www.tile-magazine.com/articles/print/87560-act-large-format-tile-and-surface-prep