The finished installation is only as good as the substrate. Large body tile and stone, 16”x16” or larger, dominate the marketplace today. The recommended industry standard states ¼-inch in 10 feet maximum permissible variation in the plane to receive ceramic tile, and 1/8-inch in 10 feet for stone including both floors and walls.
Make sure the existing surface is clean, structurally sound, dry and free from all bond-inhibiting materials. Waxes, sealers, curing compounds, old adhesives, cutback, paint, dirt, grease and oil, are all bond-inhibiting materials and need to be removed or properly prepared before installing tile or stone finishes. Use TexRite FlowRite, La-O-Tex Special 3-1, La-O-Tex Underlayment, Port-A-Patch or FeatherRite for floor prep applications. Use TexRite Wall Mud, RapidBond or TotalContact for wall prep applications.
Before applying any floor prep material, thinsets or membranes, the substrate must have absorption to aid in the bonding of these products. A simple but effective test is to spray the substrate with clean water from a quart size spray bottle, nozzle set on stream, while walking around the room, expecting immediate absorption of the water into the substrate. If absorption is not immediate, removal of contaminants is required.
For best results, the paint or stain must be mechanically removed. The paint or stain can peel, breakdown or come loose resulting in a partial or total bond failure. Mechanical removal is the most effective and preferred method of removal over chemical applications. Why? The use of chemicals to remove paint, sealers, stains or coatings from a substrate can drive the mixed chemical residue into the substrate, effectively creating a ‘bond breaker’ below the surface of the substrate. After proper preparation of the surface, use TexRite CeramaBond, TotalContact or CeramaFlex to bond the tile or stone with.
Yes. However, all ceramic tile and terrazzo must be structurally sound and well bonded before tiling. Additionally, the following guidelines should be followed. Ceramic Tile: Sweep or vacuum the floor to remove any loose debris. Clean the floor with a strong degreaser to remove any build-up, waxes, sealers or other bond-inhibiting materials. An acid wash with phosphoric or sulfamic acid might be needed to remove grout sealers, efflorescence or other mineral deposits on the tile surface or grout joint. COMPLETELY rinse the floor 2-3 times with water and baking soda to remove all cleaning residue and to neutralize the acid. Abrade tile surfaces if possible to assure proper bonding, removing all dust and debris before setting tile. Use TexRite CeramaBond, TotalContact, CeramaFlex, RapidBond or UniFlex to set the tile. If the floor needs to be leveled off, use TexRite FeatherRite or FlowRite before setting the new tile. Cement Terrazzo: Typically, all cement terrazzo floors have been maintained with waxes, sealers and polishes, which are all bond-inhibiting materials and must be completely removed before installing ceramic tile. Follow the same guidelines as bonding over ceramic tile. Can I install tile over existing vinyl or cut back adhesive? Yes. However, the following guidelines apply. It is always ‘best practice’ to remove all vinyl products before setting tile. Follow local and federal guidelines if the vinyl or cut back contains asbestos. See additional guidelines at www.rfci.com website. Existing Vinyl: The installation is only as good as the bond of the vinyl to whatever substrate it is over. The vinyl flooring must be a full spread adhered system, NOT PERIMETER TACKED. CAUTION: Do not install tile over any type of cushioned vinyl. Clean vinyl with a strong degreaser/ stripper to remove any waxes, polishes or sealers. Use TexRite CeramaBond, TotalContact, CeramaFlex or UniFlex to set tile. Cut Back: Verify that the cut back adhesive is non-water-soluble by placing soapy water on the adhesive and agitating, if the adhesive softens it is water soluble and must be completely removed. If it does not dissolve use TexRite CeramaFlex or TexRite UniFlex to set the tile.
Exterior slabs like porches or garage floors, are sloped for drainage and need to be built up and leveled before tile or stone can be applied. First, make sure the existing slab is clean, dry, structurally sound and free from any bond-inhibiting materials. Because of the slope, the new leveling layer will be thicker on the side away from the house or in the area of the original garage opening. Use TexRite La-O-Tex Special 3-1 underlayment to build-up to 1-1/2” with a single lift. Additional lifts can be applied a 24 hour drying period and priming for the second lift. Some garages and especially porches were constructed without a moisture barrier underneath the slab. This can allow excessive moisture flow through the slab that can create moisture and efflorescence problems with a ceramic tile installation if steps are not taken to correct the situation. Slabs without moisture barriers beneath the concrete should be treated with a moisture barrier above the leveling material prior to the installation of ceramic tile.
Because the limestone will probably be set with a narrow 3/16” or smaller grout joint, it is critical that the floor be as flat as possible to reduce lippage. The best combination of products for this installation would be to first, float the floor with TexRite FlowRite self-leveling underlayment, which can be applied as thick as 1”, then set the limestone with TexRite TotalContact medium bed mortar, which can be up to ¾”-inch thick after the tile has been properly imbedded. This combination of products delivers a flat, smooth underlayment in conjunction with a high performance medium bed mortar that reduces lippage and supports the large, heavy, stone tiles without allowing the stone to ‘sink’ into the bonding mortar.
If the slab has minor low spots or ‘bird baths’, then use use TexRite Port-A-Patch to fill in or patch where needed. When the entire floor needs to be skim-coated, use TexRite FeatherRite, a sandable, fast drying, unsanded, skim coating product. Both of these products are cement based, high polymer modified, substrate preparation materials suitable for applications under vinyl, VCT, wood, carpet, ceramic tile or stone.
What you see is efflorescence, which is the result of water saturating the mortar bed and activating the soluble salts within the mud bed. These soluble salts flow with the excess water and, as the water evaporates, the salts crystallize which results in efflorescence. A thick mortar bed is like a sponge and can hold large amounts of water; the waterproof membrane under the mortar bed protects the substrate or structure below the balcony from water damage but does not protect the mud bed from absorbing water. Is the balcony properly sloped to allow water runoff? Are the exposed edges of the mortar bed properly flashed or treated with the waterproof membrane? The efflorescence crystals can cause severe damage to the tile installation over time if not corrected. See Tile Council of America Handbook 2007; F103-07 and F104-07 for approved exterior tile deck installations. We have seen successful installations using TexRite HydroRite waterproof membrane under the mud bed as well as over the mud bed and on the edges of the mud bed prior to installation of the tile to prevent this problem.