A couple tiles feel slightly uneven underfoot — what causes lippage?

Tile lippage occurs when adjacent tiles sit at slightly different heights, creating an uneven surface you can feel when walking. This is one of the most common tile installation issues and can range from barely noticeable to genuinely problematic.

The primary cause is subfloor irregularities that weren't properly addressed before installation. Even small dips, humps, or slopes in the subfloor get transferred directly to the tile surface. When adhesive is applied over an uneven base, some tiles end up sitting higher or lower than their neighbors. Poor adhesive application also contributes - using the wrong trowel size, inconsistent adhesive thickness, or not maintaining proper coverage can create height variations.

Installation technique plays a crucial role as well. Tiles need to be properly leveled during installation using spacers and leveling systems. Without these tools, even experienced installers can create lippage, especially with large format tiles that are more prone to warping. The tile material itself can contribute - natural stone often has thickness variations, and some ceramic tiles aren't perfectly flat.

In Ottawa's climate, seasonal movement can worsen existing lippage. Our freeze-thaw cycles and humidity changes cause subfloors to expand and contract, potentially making small height differences more noticeable over time. This is why proper subfloor preparation is especially critical in our market.

Minor lippage (less than 1/32") might just require professional polishing or grinding. More significant issues typically need tile removal and reinstallation with proper subfloor leveling. The industry standard allows up to 1/32" lippage for tiles under 15", and 1/16" for larger tiles.

For a professional assessment of your tile lippage and repair options, request a consultation from Ottawa Floor Install. Proper diagnosis determines whether this is a simple fix or indicates underlying subfloor issues that need attention.