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Six-Sided Sealing (cont.)

1. Correct falls – making sure residual water can exit via prop erly installed drains is imperative to the success of an in stallation exposed to water. Water that is allowed to pond or stand will increase the risk of water-related staining as well as moisture issues such as freeze/thaw damage, efflo rescence and warping of moisture-sensitive stone. 2. Waterproof membranes, primers or water remediation sys tems-keeping the substrate underneath the stone/tile as dry as possible is an important part of a successful prob lem-free installation. Water can be sourced both externally and internally. Internal water can come from ground water (exterior on-grade installations) and external from weather that can filter through the installation to be stored in the substrate. So the application of products to address possi ble ground water (epoxy water remediation systems) or wa terproof membranes to ensure the substrate cannot store water supplied from above will greatly reduce contamina tion issues as well as reduce freeze/thaw and dimensional deformation. 3. Use of appropriate adhesives - using appropriate special ized polymer-modified mortars, rather than convention al mortars, will help to reduce water in the system. In the case of water-sensitive stone using an adhesive that con tains no water at all (100% solid epoxy) may be required. When a sealer is applied to the back of a stone or tile, the sealer reduces the surface water absorption close to zero. The sealed surface effectively acts more like a very dense material. Therefore adhesives that are recommended for dense materials such as granite or porcelain tile should be used along with their specific installation methods even if the stone or tile is a naturally less dense material such as limestone, sandstone or similar stone. In some cases, us ing a rapid-set mortar may be beneficial. 4. Proper placement and use of sealants – movement expan sion joints are important because the movement expansion joints manage the natural expansion and contraction of the installation. If movement expansion joints are not properly installed, the lack of movement expansion joints can lead to the loss of adhesive bond to the tile or stone. Initially one of the consequences of lack of movement expansion joints is that voids are created under the stone/tile and can collect water resulting in staining and contamination prob lems. If joint placement is left unresolved the movement expansion joint can ultimately lead to the complete failure of the tile or stone installation. 5. Six-Sided Sealing – As discussed in this document.

In summary, keeping a stone or tile installation as dry as possible, both during installation and after, is the key to minimizing wa ter-related problems. The use of six-sided sealing is most benefi cial when used during the installation and curing phase of the ad hesive/mortar (approximately 28 days) where the risk of moisture issues is highest. The six-sided sealing process must be seen as one component in a complete water management system. Imple mentation of the complete system is required to properly manage all risks of moisture types of stains that can occur during installa tion and to a lesser extent throughout the life of the stone or tile installation. Six-sided sealing will prove helpful in solving many of the chal lenges of certain tile and stone installations. Six-sided sealing is not a guarantee. Since no two stones are the same, and no two jobs are equal in all variables and aspects, six-sided seal ing process must be tested and vetted to ensure that six-sided sealing will provide the desired outcome prior to full scale use. ADDITIONAL BENEFITS OF SEALING When the face of the tile has been pre-sealed, grouting be comes a faster and easier process. The sealer will prevent the grout from potentially staining the face of an otherwise porous tile. Sealing stone or tiles makes the process of removing the grout from the face of the tile during installation easier. Pre sealed material is similar to using a grout release product. Since all sides of the tile have been sealed, water will not migrate into the stone and darken the stone. Six-sided sealing will prevent dyes in grout and silicone sealant from entering the tile and cre ating “picture framing” around the perimeter. Because the tiles are pre-sealed, the tiles are protected from accidental spills during the first few days after installation. Nor mally the installer or owner must wait several days for the grout to cure before sealing the entire installation. During the curing period, the tiles are typically unprotected, but pre-sealing the stone or tiles eliminates the concern of accidental spills affect ing the finished installation. Over time, the repellent qualities of the sealer will be affected by the hardness and texture of the material, surface wear, weath er conditions and cleaning regimens. All installations should be periodically tested, at least annually, to ensure that the sealer is still doing its job.

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Chapter 6 | Natural Stone Installations