What Are Lime Pops on Saltillo Tiles?
Lime pops are small bumps or indentations that appear on the surface of Saltillo tiles, caused by lime or calcium nodules present in the clay expanding during the firing process and erupting through the tile surface. They are a normal characteristic of handmade, authentic tiles and can be repaired or avoided during installation.
During the manufacturing process, the presence of these minerals is usually filtered out. However, it is sometimes difficult to completely eliminate lime from the clay. Consequently, when the clay is fired, the lime nodules heat up and expand. This expansion puts pressure on the surrounding clay, and if the pressure becomes excessive, the lime pops can erupt through the tile surface, resulting in small indentations that reveal the natural clay beneath.
Lime pops are a natural characteristic of handmade Saltillo terracotta and are not a cause for concern. They can be managed with proper preparation and add to the authentic, handcrafted character of the tile.
If you notice the presence of these small lime pops when inspecting your tiles, you have the option to not use those particular tiles. We recommend either leaving them behind or repairing them before installation.
How can you prevent or repair lime pops?
Hiring an experienced installer to properly prepare the subfloor is the most effective way to prevent lime pops from appearing after installation. If lime pops do appear, two repair options are available:
- Have a professional gently grind down the lime pop using a diamond-tipped tool, taking care not to damage the surrounding tiles.
- Fill the indentation left by the lime pop with a color-matched tile filler or grout, allow it to cure fully, then lightly sand the affected area smooth and reseal it to restore the spot.
Lime pops can appear in various sizes and may emerge immediately after installation or develop over time, potentially even years later. It is important to note that there is no definitive timeline for their appearance, and in some cases, they may not occur at all. Examples below:
What is efflorescence on Saltillo tiles?
Efflorescence is a common issue that occurs on Saltillo tiles. It manifests as a white, powdery substance on the tile surface, typically after being exposed to moisture.
The cause of efflorescence is the salts and minerals, such as calcium, that rise to the surface of the tile. When moisture enters the tile's pores, it dissolves these salts. As the moisture evaporates, the salts crystallize on the tile surface, resulting in the characteristic white powdery appearance of efflorescence.
To prevent efflorescence on Saltillo tiles, it is crucial to adequately seal them with a high-quality sealer. You can find our recommended tile sealers here. Proper sealing helps reduce moisture penetration and prevents the migration of salts to the surface. Additionally, ensure that the tiles are installed correctly and that the grout lines are sealed to prevent moisture from seeping through.
If efflorescence appears on unsealed Saltillo tiles, it can be removed using a hard-bristled brush. Afterward, the tiles should be sealed once they are completely dry.
However, if efflorescence occurs on a sealed Saltillo tile, the sealer must be removed before attempting to eliminate the efflorescence with a brush or sandpaper. For oil-based sealers, an oil-based stripper should be used to effectively remove the sealer and reach the clay body surface. Once the sealer is removed, the efflorescence can be eliminated with a brush or sandpaper. After removing the efflorescence, make sure the tile is spotless and allowed to dry completely before applying a new sealer.