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Questions for Prepare The Surface

1. Please refer to Product Data Sheets with questions
- A:

Questions for Set The Tile

1. There are thin set mortars (ANSI 118.1) and latex modified thin set mortars (ANSI A118.4 or A118.11). What is the difference?
- A: The addition of latex is the main difference in these two types of products. Latex modified thin sets are required for installations involving difficult to bond to substrates (EGP, Vinyl tile, ceramic tile). They are also required for installing difficult to bond to tile (porcelain) and for all exterior applications. Non-latex modified thin sets (ANSI A118.1) can be used for interior applications on concrete, masonry, cement board, drywall, and mortar beds except when porcelain tile is being installed.
2. Should I use a thin set mortar on the floor?
- A: Yes, thin set mortars are very effective and highly recommended for floors. For tile larger than 8" x 8" and/or in excessively wet areas (steam rooms) or exterior installations, thin set mortars are required. Please refer to the TEC Skill SetTM Mortar Selection Guide to determine the appropriate thin set mortar for your particular tile type, size, substrate and service environment.
3. Should I use a thin set mortar on the wall?
- A: Yes, thin set mortars are very effective and highly recommended for walls. For tile in excessively wet areas (steam rooms) or exterior work, latex modified thin set mortars are required. However, for interior residential installations (showers, bath, kitchen), a Type I Mastic is also appropriate. Please refer to the TEC Skill Set Mortar Selection Guide to determine the appropriate thin set mortar for your particular tile type, size, substrate and service environment.
4. Are all latex modified thin set mortars the same?
- A: Latex modified thin set mortars are categorized by the performance criteria they meet. ANSI A118.4 mortar is designed for exterior conditions or for use with hard to bond to substrates (existing vinyl tile, ceramic tile, etc) and/or tile (porcelain tile). ANSI A118.11 mortars are designed for installing tile over exterior grade plywood C-C plugged or better. If you are planning to install tile over a plywood floor, be certain that the thin set specifically states that it is recommended for that purpose (ANSI A118.11). TEC Skill Set Fast Setting Mortar, which is accelerated and can be grouted in as little as three hours dry time, is additionally approved for use with plywood. Please refer to the TEC Skill Set Mortar Selection Guide to determine what the appropriate thin set mortar is for your particular tile type, size, substrate and service environment.
5. Where do the ANSI numbers come from?
- A: American National Standard Institute. ANSI has developed Specifications for materials and the Installation of Ceramic Tile.
6. What TEC Skill Set thin set do I use to bond ceramic tile to plywood?
- A: Latex modified thin set mortars (ANSI A118.11) including TEC Skill Set Glass Tile Mortar, Marble Mortar, Natural Stone and Large Tile Mortar, Porcelain Mortar, TotalFlex Universal Mortar and Fast Setting Mortar. You may also use TEC Skill Set Floor Mortar and TEC Skill Set Floor and Wall Mortar, non-latex modified thin set mortars, by mixing them with TEC Skill Set Mortar Additive. The plywood must be exterior grade plywood C-C plugged or better. For CDX Plywood, use TEC Skill Set Floor and Wall Mortar mixed with TEC Skill Set Mortar Additive.
7. Can I set ceramic tile on a single layer of plywood?
- A: No. The floor construction must be at least two layers of plywood with a total floor thickness of 1 1/8". Floor deflection should not exceed L/360 for ceramic tile and L/720 for the installation of marble.
8. Can I set ceramic tile over Oriented Strand Board (OSB)?
- A: No. The primary approved wood substrate for ceramic tile installations is APA (American Plywood Association) exterior grade plywood, C-C plugged or better. Other non-approved substrates include rubber, strip wood floors, particleboard, lauan plywood, hardboard, & treated plywood.
9. How do I install cement board over plywood?
- A: Refer to the specific Cement board manufacturers guidelines for installation (this is important being as the different cement board manufacturers have different requirements to maintain their product warranties), then select the appropriate TEC Skill Set thin set mortar, according to their requirements, for establishing the support plane for the backer board.
10. What type of thin set should be used for a concrete swimming pool?
- A: Any TEC Skill Set mortar that is latex modified is recommended for exterior pools or if the tiles to be installed are porcelain. You may also use any of TEC Skill Set non-latex modified thin set mortars by mixing them with TEC Skill Set Mortar Additive. If the pool is an indoor pool and the tile is not porcelain, any TEC Skill Set thin set mortar can be used.
11. How long should I wait to fill the pool?
- A: Twenty-one days after the tiles are installed and grouted.
12. Can tile be installed in hot weather conditions?
- A: Tile should not be installed on substrates or in weather that exceed 90 degrees. Steps should be taken to lower the temperatures or schedule the installation for early in the morning or later in the evening when temperatures are cooler. Additional options that are commonly used on commercial projects is to tent the area to be tiled to provide shade, and also to dampen the concrete about an hour before tile setting, the evaporation of the water will cool the concrete.
13. What should be used to set fixtures such as a soap dish or towel rack?
- A: Fixtures should be set with a thin set mortar, construction adhesive or 100% silicone. Do not use tile mastic.
14. Do porcelain tiles require a special adhesive?
- A: Porcelain tiles require the use of (ANSI A118.4 or better) latex-modified thin set mortar. See the TEC Skill Set Mortar Selection Guide.
15. What size trowel should I use to set my floor tile?
- A: No matter which trowel you select, keep in mind that bonding mortar coverage is the issue. Try to achieve a minimum of 80% coverage for interior and/or dry areas and 100% for wet or exterior installations. Check a tile occasionally during installation to verify. Typically, for tiles up to and including 6" x 6" tile, use a 1/4" x 1/4" x 1/4" square notch trowel. For tile larger than 6" x 6" up to and including 12 " x 12" tiles, a 1/4" x 3/8" x 1/4" square notch trowel should be used. For tiles larger than 12" x 12" and for substrate variations up to 1/4" in 10' will require a bigger notch such as a 1/2" square notch trowel or a 3/4" round notch trowel. See the TEC Skill Set Mortar Selection Guide.
16. Can ceramic tile be installed over my existing laminate floor?
- A: No, the laminate floor must be removed and the substrate prepared for ceramic tile.
17. Can I install tile over my existing VCT or existing sheet goods?
- A: Yes. The existing VCT must be a single layer. If the existing VCT (or sheet goods) is over plywood, refer to plywood installation guide for the minimum floor thickness. Sheet goods (only non cushion is acceptable) must be full glue down and not just glued around the perimeter. All linoleum must be stripped and cleaned of waxes, dirt and any contaminants that will interfere or prevent a good bond [chemically strip first, then rinse thoroughly with clean water and allow to dry completely]. Once the substrate is properly prepared, TEC Skill Set latex modified thin sets are recommended. NOTE: Unless you are positively certain that the product you intend to remove is a non-asbestos containing material, you must presume that it contains asbestos. Regulations may require that the material be tested to determine asbestos content. According to the Resilient Floor Covering Installers Handbook "Do not sand, dry sweep, dry scrape, drill, saw, bead blast, or mechanically chip existing resilient flooring, backing, lining felt, asphaltic cutback adhesive or other adhesive prior to determining asbestos content".
18. Can I install ceramic tile over existing ceramic tile?
- A: Yes. Existing ceramic tile should be clean and dry, then primed with TEC Skill Set Self Leveling Underlayment Primer full strength. After the primer is dry, set tile with one of the TEC Skill Set latex modified thin set mortars.
19. Can tile be installed over adhesive residue?
- A: If the adhesive is soft or tacky it must be completely removed. Black Adhesive (Cut-back) residue is acceptable provided the adhesive is well bonded to an approved substrate. Scrape the adhesive residue until it is no thicker than a sheet of paper and almost transparent. Loose or weak adhesive may prevent a good bond between the tile and substrate, resulting in installation failure. Water based cutback adhesive is not acceptable, it must be removed with soap and water. To determine, place soap and water on adhesive, observe if adhesive is softened. Once the substrate is properly prepared, TEC Skill Set latex modified thin sets are recommended.
20. Can I install ceramic tile over a plastic laminate countertop?
- A: Yes. Plastic laminate is an approved substrate for interior countertops with TEC Skill Set latex modified thin set mortars provided the counter is structurally sound and level. To prepare the countertop surface; first chemically strip any sealers or finishes off of the surface, then lightly abrade, thoroughly rinse and dry completely.
21. What should I use to install ceramic tile in a steam room?
- A: For a steam room application, TCNA (Tile Council of North America) specification SR614-01 should be followed. The ceramic tile can be set with TEC Skill Set latex modified thin sets. You may also use TEC Skill Set Floor Mortar or TEC Skill Set Floor and Wall Mortar by mixing with TEC Skill Set Mortar Additive. Allow 7 days cure prior to using the steam room.
22. How should ceramic tile be installed over Gypcrete?
- A: Due to the moisture sensitivity of gypsum based underlayments, ceramic tile cannot be installed directly over Gypcrete without the use of a crack isolation and waterproof membrane. TEC Skill Set Waterproofing and Crack Prevention Membrane can be applied first, then install ceramic tile with one of the TEC Skill Set latex-modified thin set mortars.
23. Can I mix TEC Skill Set Mortar Additive in TEC Skill Set DesignColorTM Grout?
- A: No. the TEC Skill Set Mortar Additive should be used only as an additive for TEC Skill Set Floor Mortar or TEC Skill Set Floor and Wall Mortar. Use Grout Boost® Stain Resistant Additive for TEC Skill Set DesignColor grouts.
24. When do I need to add latex to TEC Skill Set thin set mortars?
- A: Latex must be added to any mortar that is not already latex modified, when used on any exterior applications, interior tile applications over properly installed plywood, and over TEC Skill Set Waterproofing and Crack Prevention Membrane. This is also recommended over acceptable properly prepared existing floor covering.
25. Can I add additional latex to a latex-modified thin set?
- A: No. Never add additional latex to a latex-modified thin set.
26. Can Grout Boost be used with TEC Skill Set mortars?
- A: No. Grout Boost is formulated to mix with cement based grouts only, like the TEC Skill Set DesignColor grouts. Be sure to used Sanded Grout Boost with sanded grout and Unsanded Grout Boost with unsanded grout.
27. Can I dilute the latex additive before use?
- A: No, TEC Skill Set Mortar Additive is specifically formulated to perform with TEC Skill Set Floor Mortar and TEC Skill Set Floor and Wall Mortar.
28. What do I do if the TEC Skill Set Mortar Additive freezes?
- A: Allow the latex additive to gradually return to room temperature before using. Do not accelerate thawing of the additive.
29. Can I use mastic for floor tile installation?
- A: Yes, pay attention to tile size and type when using mastics for floor installations. In general, limit the tile size to no larger than 8" x 8". You can expect longer drying time when installing porcelain tile or any 8" x 8" tile with mastic. Be sure the the underlayment is approved for ceramic tile installations.
30. Why does mastic appear soft or damp after 24 hours?
- A: Lack of airflow, high humidity, and/or substrate temperature (below 60 degrees F) will extend the drying time. Tiles larger than 6” x 6” will require additional time for mastic to dry. It would help if you could warm the area and increase the airflow to accelerate drying. Do not grout until the mastic has dried and tile are set firmly in place.
31. Can I use TEC® Skill Set™ Type I Mastic to set 12" x 12" tile?
- A: Yes, but only for wall installations. However, you can expect an extended drying time. Do not grout until the mastic has dried and tile are set firmly in place.
32. Can TEC® Skill Set™ Type I Mastic be used under white or translucent stone?
- A: Yes, but not over plywood. Over other substrates, always test the natural stone for potential discoloration. Install a sample and allow it to dry thoroughly. Stone that displays discoloration should be set with TEC® Skill Set™ Marble Mortar or one of the TEC® Skill Set™ Mortars in white, not gray.
33. Can TEC® Skill Set™ Type I Mastic be used to set green marble or glass tile?
- A: No. Green marble can be very sensitive to moisture and must be set with TEC® Skill Set™ Marble Mortar. Glass tile should be set with TEC® Skill Set™ Glass Tile Mortar.
34. The label references TCNA Installation Detail F142. What does this refer to?
- A: TCNA is the Tile Council of North America. The number refers to an accepted and proven tile installation method.
35. Can I install tile over glazed ceramic tile?
- A: Yes, but you must first abrade the glaze from the existing ceramic tile. A belt sander or a carborundum disk can be used to accomplish this. The glaze must be abraded so that the moisture in the mastic can absorb into the existing tile, allowing the mastic to dry. You can expect an extended drying time. Do not grout until the mastic has dried and tile are set firmly in place. See TCNA detail TR712 and/or TR713 for more details.
36. Can I use TEC® Skill Set™ Type I Mastic to install ceramic tile over a plastic laminate counter top?
- A: Yes, but first chemically strip any sealers or contaminants, if they exist, off of the counter top. Then lightly sand the counter top, rinse and let dry. You can expect an extended drying time. Do not grout until the mastic has dried and tile are set firmly in place. See TCA detail TR711 for more details.
37. Can I use TEC® Skill Set™ Type I Mastic to install tile in a steam shower?
- A: No. It is best to first utilize a waterproof membrane TEC® Skill Set™ Waterproofing and Crack Prevention Membrane behind the tile in a steam shower. Waterproof membranes require the use of a latex modified thinset mortar to install the tile. Select from the TEC® Skill Set™ Latex Modified Mortars for the appropriate setting material.
38. Can TEC® Skill Set™ Type I Mastic be used over a painted surface?
- A: Yes, but for wall installations only, not floors. The paint should be clean, dry and should be at least 2 weeks old (no freshly painted surfaces). Oil based painted surfaces should be at least one year old. High or Semi Gloss painted surfaces should be lightly sanded, rinsed and allowed to dry. You can expect an extended drying time. Do not grout until the mastic has dried and tile are set firmly in place. See TCA detail TR711 for more details.
39. Can TEC® Skill Set™ Type I Mastic be used outdoors?
- A: No. Mastic should be used for indoor tile installations only. TEC® Skill Set™ latex modified thinsets can be used exterior.
40. Can I use TEC® Skill Set™ Type I Mastic to install a bathtub soap dish?
- A: No. Tile fixtures such as these require high bond strengths that develop quickly.
41. How can I remove TEC® Skill Set™ Type I Mastic from a tile surface?
- A: If the mastic is relatively fresh, warm soap and water can be used. Well dried mastic should be scraped down to a film, Mild Odor Mineral Spirits (MOMS) can soften and remove the residue.
42. Can I store TEC® Skill Set™ Type I Mastic in my unheated garage?
- A: No, although the adhesives are freeze/thaw stable for up to five cycles, long-term storage under repetitive freezing conditions will render it unusable.
43. How long can I keep any leftover TEC® Skill Set™ Type I Mastic?
- A: If the container is tightly sealed you may keep them for 6 months if stored inside in a cool, dry location. Applying saran wrap (plastic wrap) directly over the adhesive before reapplying the lid aids in preserving freshness. Keep in mind that when the containers are open they are losing moisture.
44. What is the highest temperature that TEC® Skill Set™ Type I Mastic can be exposed to once applied?
- A: Do not use in any area where temperatures exceed 120 degrees Fahrenheit.
45. I am installing porcelain tile. How much additional time should I allow it to set prior to grouting?
- A: Porcelain is very non-absorptive. In some circumstances the dry time could exceed twice that of an absorptive ceramic tile. Factors that can extend the dry time are low temperatures, high humidity, and lack of air circulation, non-porous substrates, large tile size, and narrow grout joints. Do not grout until the mastic has dried and tile are set firmly in place. Using TEC® Skill Set™ Porcelain Mortar is another option.
46. How can I tell if my floor tile is ready to grout?
- A: The first check is to try and twist the tile to see if it moves. If there is movement, additional cure time is required. If the tile won´t twist but you hear a wet suction sound when the tile is stepped on, additional cure time is also required
47. I understand that installations over concrete with either excessive moisture vapor emissions or dampness are not recommended. How can I test my concrete for these, as they might not always be visible on the concrete surface?
- A: Three ways of testing your concrete are: • Take pieces of plastic and tape them tightly to your concrete floor with duct tape in various spots. Wait overnight. The area underneath the plastic should be free of dampness, discoloration, or damp odors. • A moisture meter: may be used to obtain surface readings and identify wet locations to conduct further testing. • Calcium chloride moisture test kit: follow kit manufacturer's instructions precisely to determine moisture emissions. An acceptable moisture vapor emission reading is between 3-5 lbs. per 1000 S/F over a 24-hour period.
48. I understand that waterproofing compounds, membranes, sealants, grease, oil, wax, and other foreign matter will impair the adhesion of adhesives on concrete. These are not always visible. Is there any way that I can check my concrete?
- A: Obviously you will want to remove anything that is on the surface that you can see such as residues of old adhesives, etc. There is a simple test though for coatings that are not visible. It is called the "water droplet test". Put water droplets on various spots on the floor. If the water beads up, there is something on the surface that will impair adhesion. It is recommended to remove the contamination prior to installing the tile.

Questions for Grout & Caulk