ICS Magazine

Understanding Saltillo Tiles

April 14, 2003


In Mexico an area known as the Saltillo region is loaded with natural deposits of clay. These deposits have allowed a number of businesses to thrive producing Saltillo tiles.

The combination of raw materials and hot temperatures make the area ideal for tile manufacturing. The tiles are made of clay mined from nearby pits. Once formed, the tiles are left in the sun to dry on wooden racks. Some of these racks are low to the ground; animal tracks can occasionally be found in a tile.

Next, the tile is either baked in a “beehive” kiln or semi-cooked in makeshift pits left after the clay had been quarried. Compared to other clay masonry tiles, Saltillos are not baked at high temperatures and, unlike other tiles, no glazing material is applied nor are the tiles baked for a second time. The color of the clay is the color of the tile.

Saltillo tiles can be installed in commercial and residential properties. They are found primarily in southern regions of the United States, and are installed both indoors and out. The tiles are beginning to make some inroads into the northern climates, but almost exclusively indoors; Saltillo tiles are not frost-proof and can easily be damaged in colder environments.

While the tiles are inexpensive to buy, they can be very expensive to install. Unlike other tiles that can be cut with conventional tile cutting equipment, Saltillos must be cut with a diamond wet-saw. In addition, Saltillos are more difficult to grout because of their thickness; they require more grouting material and take longer to install than ceramic, porcelain or quarry tiles.

Saltillos are very porous tiles and therefore must be sealed. Allow at least three weeks after installation before sealing the tile and grout, during which time the business or homeowner must simply wait. They must also be very careful; anything spilled on the unsealed tile may stain it. A poultice, a mud-like substance used to pull or draw the stain out of the porous surface, may have to be used to remove the stain before sealing.

Use a penetrating sealer on new Saltillo tiles and grout. Penetrating sealers fill the pores and irregularities to the level of the floor or grout; they are not topical coatings such as floor finishes (wax). Due to the thickness and porosity of the tiles, two coats of sealer are usually required.

All grouting residue, dust and dirt must be removed before sealing. Start by sweeping or vacuuming the tile; dust mopping is not recommended due to texture of the tile and grout. If grout residue or other soils remain you will need to wet clean the floor. The amount and type of soil will dictate the wet-cleaning process to use. Minimal soil may only require a damp mopping; if there is a lot of soil that needs to be removed, however, a more restorative procedure will be required. In these cases I recommend using equipment that will allow you to apply the cleaning solution and simultaneously extract the slurry before is soaks into the tile. An automatic floor scrubber with a brush instead of a pad is recommended; the condition of the floor will dictate the abrasiveness of the brush. You can also use tile and grout cleaning tools that attach to either a truckmount or portable carpet-cleaning machine. When using one of these tools it is recommended that you clean at lower pressures, usually somewhere between 400-600 psi, unless the floor is extremely soiled.

To seal or reseal existing tile, it is important to know what is on the tile. Although a penetrating sealer was probably used initially, a topical coating is sometimes applied to enhance the floor and give additional protection. These floor finishes will need to be removed unless you are only maintaining the topical coating, in which case a scrub and recoat may be all that is needed to restore the floor to the desired appearance.

To restoratively clean the floors, the topical coating must be removed. Once again, I recommend using equipment that will allow you to apply the cleaning solution (in this case a commercial grade floor stripper) and simultaneously extract the slurry before it soaks into the tile.

On existing floors sealed with just a penetrating sealer it is recommended to re-apply the product from time to time. The original product used, the amount of traffic and soil conditions will dictate how often this is done. You prepare the floor by cleaning it and then simply re-sealing the tile and grout with the same or similar product as was originally used.

Regardless, when cleaning new or existing tile, the tile and grout must thoroughly dry before applying the sealer.

To apply a penetrating sealer, follow all application and safety directions on the label. Penetrating sealers are usually applied with a roller, a rayon mop or low-pressure sprayer and brushed in. The tile is saturated with the sealer and left alone to allow the sealer to penetrate. Remember, penetrating sealers only fill the pore to the level of the tile. Before the product dries completely, wipe off the excess to prevent hazing or streaking. If streaking does occur, apply more sealer to reactivate the existing sealer; this will allow you to remove it. Fortunately, due to the porosity of Saltillos, streaking does not happen very often.

Water- and solvent-based sealers are the two types of penetrating sealers used. They are either oilophobic or hydrophobic. Oilophobic sealers protect the floor against solvent-based spills such as cooking oils, greasy, oily soils and other substances. Hydrophobic sealers protect against water-based spills, soda, coffee, tea, water, fruit drinks, milk, and so on. Oilophobic sealers always work as a hydrophobic, but a hydrophobic cannot work as an oilophobic. Therefore, it is important to match the right sealer for the traffic, use and environment in which the floor located.

Ceramic and porcelain tiles are available that are made to look like Saltillos. You can tell these from the real stuff just by looking at the depth and porosity; Saltillo floors are much thicker and very porous, where ceramic and porcelain are much thinner and non-porous by nature. A true Saltillo tile floor offers a rustic look unmatched by any other tile floor.