How to measure tile lippage
What Is Tile Lippage?
Tile lippage refers to differences in elevation between the edges of adjacent tile modules. This definition comes directly from the ANSI standard A108.02, Section 4.3.7.
Even small height differences between neighboring tiles can be noticeable to the eye, making lippage one of the most common quality concerns in tile installation.
How to Measure Tile Lippage
Lippage is measured by placing a straightedge or a specialized lippage gauge across the joint between two adjacent tiles and checking the vertical difference at their edges. The measurement captures how much one tile edge rises above or dips below the neighboring tile.
A reliable lippage gauge — sometimes called a lippage gauge tool — is laid flat across both tile surfaces at the joint, and a feeler gauge or graduated wedge reads the gap between the straightedge and the lower tile edge.
Factors That Affect the Perception and Amount of Lippage
The ANSI standard notes that the perception of lippage is influenced by several factors, including the allowable thickness variation of the tile modules, the allowable warpage of the tile modules, and the spacing or separation between each tile module — which influences whether the change in elevation appears gradual or abrupt.
Additional factors identified by the standard include the angle of natural or manufactured light accentuating otherwise acceptable variance, and highly reflective tile surfaces that can make minor height differences appear more pronounced. Variations in the plane of the substrate also affect lippage, and when tile is installed by the thinset method over an uneven substrate, the installed surface may not meet lippage standards.
Planning Your Tile Project to Minimize Lippage
Ensuring a flat, properly prepared substrate before installation is one of the most effective ways to reduce lippage. Choosing tiles with tight manufacturing tolerances for thickness and warpage also helps achieve a flush, even surface.
Before purchasing materials, use a free tile calculator at / to estimate the exact quantity of tiles needed for your project — accurate measurements help you plan grout joint widths and layout patterns that can reduce the visual impact of any minor lippage.
Key takeaways
- Tile lippage is defined by ANSI standard A108.02 as differences in elevation between the edges of adjacent tile modules.
- Factors such as tile warpage, substrate flatness, joint spacing, lighting angle, and tile surface reflectivity all influence how much lippage is perceived.
- Measuring lippage requires a straightedge or dedicated lippage gauge placed across the joint between two tiles to capture the vertical height difference.
- Installing tile over an uneven substrate using the thinset method can cause the finished surface to fail lippage standards.
Related tools
Estimate materials with our free tile calculator on Tile Calculator.