How to Lay Mexican Saltillo Tile on a Concrete Slab
Guidelines & Recommendations
Many variations to the following steps may exist for your specific project space and tile. Consult with your local contractor or tile installer for more precise advice relevant to your tile project.
Rustico Tile & Stone is not responsible for Saltillo tile installations not completed by one of our contracted installers. We do not provide advice via phone or email for tile that has not been purchased from Rustico Tile & Stone.
For a complete set of instructions, consider our How to Install Saltillo Tile eBook available on Amazon.
Now for the fun stuff… How to Lay Saltillo Tile on a Concrete Slab Subfloor
1. Prep the concrete subfloor. Examine for any cracks or foundation issues. There will be surface and hairline cracks. (Tip: If you do not see the cracks, spray water on the slab to make the cracks visible.) Then, treat these cracks with a crack isolation membrane of your choice. (Our installers prefer to use our Crest Crack Isolation & Waterproofing membrane.) For complex and/or commercial jobs, Ditra is a great option, though more expensive. Ditra is good for slabs with foundation problems or on slabs in sandy soil (or if the slab is apt for movement).
Pro Tip: If the slab is brand new, apply the crack isolation membrane across the entire slab. Your concrete slab will settle over time resulting in the appearance of hairline cracks. The crack isolation membrane will help mitigate those cracks from transferring to the new tile floor. While this technique isn’t guaranteed to prevent all cracks, the successful prevention is significant.
Pro Tip: This Crest membrane doubles as crack isolation and waterproofing. For any outdoor installation or spaces in wet areas, we recommend full coverage application of the membrane to accomplish the waterproofing protection.
2. Next, Apply thinset (we recommend Crest Porcelanato or Crest Gran Formato). If using the DITRA product mentioned above, you do not need elastic thinset. We recommend semi-modified or fully-modified thinset which can be found at a local home improvement store. ½” x ½” trowel is recommended for a basic 12×12 size saltillo tile. For other sizes, consult with your installer.
3. Now, lay the terracotta Saltillo tile (assuming it is presealed. If it is unsealed, see tips at the bottom of this guide). With a standard 12×12 size tile, a minimum grout line recommended is ½”. Any grout line that is wider is for cosmetic purposes. We do not recommend using spacers with authentic handmade Saltillo tile to allow for the size/shape variations. Your installer pays attention to detail to keep the tile layout and spacing consistent. This is not a complicated process. Cut Saltillo tile with a wet saw.
4. Grout Saltillo tile floor after thinset dries (usually an overnight waiting period). Recommended grout includes a sanded grout or mortar mix. This can also be found at a local home improvement store. Check out more Saltillo Tile Grout Tips.
5. Clean Saltillo tiles. You need to clean your Mexican tile floor thoroughly to remove any grout haze or debris accumulated during the installation process. Then, allow the Saltillo tile floor to dry for several days. Our StoneClean 104 cleaner, water, and a sponge or brush can be used for cleaning the floor. If you choose to you any other type of chemical cleaner, follow this step by a few mop-washes of 50/50 mixture of acetone and water. Any residual cleaning chemical must be fully removed prior to applying your topcoat of Saltillo tile sealer.
6. Finally, Seal the Saltillo tile floor. Once your installation is complete, cleaned, and is _thoroughly _dried, you can now apply the topcoat of the tile sealer. An ideal topcoat sealer will last several years and can also be applied to the terra cotta grout lines. We recommend Crest or TerraNano topcoat sealer. Allow the terra cotta sealer to fully dry and cure. Once cured, installation is complete.
A few tips:
- Save $$ and time. Check out Why You Should Buy & Install only Sealed Saltillo Tile.
- Do not soak presealed Saltillo tile prior to installation. Just don’t. Ever.
- If you are installing unsealed Saltillo tile, you can soak these prior to installation or apply several coats of Saltillo tile sealer prior to installation. It’s better to seal the tiles than to soak the tiles.
- Do not dry stack Saltillo tile in installation.
- Do not skip the crack isolation membrane step. No one wants to repair hairline cracks in a tile floor because slab cracks were left untreated.
- We strongly recommend applying a waterproofing membrane across the full surface area of a slab in an outdoor tile installation. This will reduce the possibilities for efflorescence & ongoing maintenance.