Lippage in Natural Stone and Ceramic Tile

Lippage in Natural Stone Tile  

Lippage is a condition where one edge of a tile is higher than an adjacent tile, giving the finished surface an uneven appearance. Lippage in stone tile flooring is accentuated from what would be perceived in a ceramic tile installation for several reasons. First, natural stones tend to be installed with tighter joints, particularly because some stones require narrower joints to allow for the use of unsanded grout. Second, natural stones typically have slight or no chamfer at their edges. Third, many natural stones have a high-gloss, polished finish.

Industry standards limit lippage between adjacent units of smooth-finished natural stone flooring to 1/32”. When this is not achieved, there is the option of grinding the stone tiles in place to eliminate the lippage. This work must be done by skilled, experienced technicians, with care taken to avoid a wavy-looking finished floor. In some cases, installing contractors plan to grind the finished floor regardless of the lippage amount, usually per the requirement of the client. Lippage should still be minimized to the extent possible during installation to avoid extremely thin stone sections after grinding.

Lippage in Ceramic Tile 

Lippage is a condition where one edge of a tile is higher than an adjacent tile, giving the finished surface an uneven appearance. Lippage is inherent in all ceramic installation methods and may also be unavoidable due to the tile tolerances, in accordance with ANSI A137.1. The following is excerpted from ANSI A108.02, Section 4.3.7:

4.3.7 Lippage — guidelines, explanation, and caution: Lippage refers to differences in elevation between edges of adjacent tile modules. These differences or perception thereof are influenced by many factors such as:

 A) The allowable thickness variation of the tile modules when judged in accordance with manufacturing standards.

B) The allowable warpage of the tile modules.

C) The spacing or separation of each tile module, which would influence a gradual or abrupt change in elevation.

 D) Angle of natural or manufactured light accentuating otherwise acceptable variance in modules.

 E) Highly reflective surfaces of tile modules accentuating otherwise acceptable variance in modules.