We receive calls on a regular basis with questions about efflorescence. Is it normal? Do I have defective tiles? How can I remove efflorescence from my terra cotta tile or stone?
In most cases, it IS normal for saltillo tiles, terra cotta pavers, and many stones to have efflorescence. This is not considered a defect because it’s a natural element in these earthen materials. The appearance of efflorescence can be found in many architectural structures around the world (statues, floor tiles, outdoor pavers, monuments, masonry, natural stones, ceramic tile, brick, wood, buildings and more).
What is Efflorescence?
This is a white crystalline substance often seen on the surface and is composed of salts, lime and other minerals. In Mexican tile, these salts come from within the clay where alkali substances exist. As water evaporates from within the clay and from bedding installation materials, the salts use moisture as its vehicle to transport itself onto the surface. As the moisture evaporates completely, it’s easy to see the alkali material. In situations where a fat mud setting mixture is used, there may be a heightened probability of efflorescence occurring because there is lime added to the mortar.
What Can I Do to Control Efflorescence on Saltillo?
First, buy presealed tile is possible. This helps reduce the possibility that you will see abundant areas of efflorescence. At Rustico Tile and Stone, our presealed tiles are sprayed with 5 coats of penetrating sealer. This helps eliminate unnecessary moisture from penetrating the clay. However, it is still possible that the salts can travel upward to the surface with excessive moisture evaporating from installation materials. Another solution is to use a waterproof membrane beneath the installed surface. Ask Rustico about their Schluter products to use with your Saltillo tile installation.
Once your material is installed and grouted, apply a good quality topcoat sealer like our GREEN sealer ($119/gallon). GREEN is a good water repellents sealer that can help efflorescence from occurring when the original source of moisture is coming from the exterior elements or from below. If you’re using a topical sealer that is not breathable, this can propel the efflorescence problem.
How Can I Clean Efflorescence on Saltillo?
The best method is the use an acid cleaner (acid and cleaner elements). The salts and minerals typically dissolve on contact with acidic cleaners. If the efflorescence lies below the surface of the sealer, that sealer will need to be removed for the acid to do the trick. Cleaner that is in the solution will work to remove any latex that could be providing a protective barrier to the salts and minerals. Once complete, flush with water VERY thoroughly. Above all else, follow the manufacturer directions for the cleaner of your choice. Test a small area first to be certain you will be satisfied with how to clean efflorescence on saltillo.