Floor tiles grout cracking

Close-up view of cracked grout lines between light-colored ceramic floor tiles, showing deterioration.
Photo: Vladimir Srajber / Pexels
A hand operating a grout removal tool along the seam between two floor tiles, preparing for regrouting.
Photo: Vladimir Srajber / Pexels

Watch: Repairing Cracked Grout

Regrout Shower Floor Tile (Quick Tips) via Home Repair Tutor

Understanding Tile Lippage

Lippage refers to differences in the height between the edges of adjacent tile modules. This variation is influenced by several factors.

These factors include allowable thickness and warpage variations of the tiles, the spacing between tiles, and the angle and type of lighting. The reflectivity of the tile surface can also accentuate lippage.

Causes of Lippage

Variations in the plane of the substrate can significantly affect lippage. When tile is installed using the thinset method over an uneven substrate, the final installed surface may not meet lippage standards.

The ANSI A108.02 standard addresses acceptable variations in tile height. Adherence to these standards is crucial for a proper installation.

Tile Standards and Installation

The ANSI A108.02 standard, specifically Section 4.3.7, defines lippage. It also outlines factors that influence the perception of lippage.

The ANSI A137.1 standard defines the allowable warpage for tiles. Proper substrate preparation is essential to minimize lippage and ensure a level tile surface. For help estimating materials, use our free tile materials calculator.

Key takeaways

  • Lippage is the difference in height between adjacent tiles, influenced by tile variations, spacing, lighting, and substrate flatness.
  • Uneven substrates are a common cause of lippage when using the thinset installation method.
  • ANSI standards provide guidelines for acceptable tile warpage and lippage.

Related tools

Estimate materials with our free tile materials calculator on TileMaterials.

Sources