Interstyle Glass Wall Tiles Installation Guidelines

(Download this document in PDF format)

General – Interstyle manufactures glass tile by fusing clear glass with ceramic glazes at a high temperature. Interstyle’s glass tiles may be installed on interior or exterior wall areas, in wet or dry locations (including in hot or cold environments). Interstyle’s glass tiles are manufactured in 4 and 6 mm thicknesses for wall use and 10 mm for floor and wall use. Glass tiles differ from ceramic products; attention must be given to these special glass tile installation instructions to ensure a good installation.

Do not use standard ceramic tile installation methods as these may result in a finished installation with appearance and/or durability problems. Do not expose glass tiles to high abrasion, strong impact, mechanical stress or thermal shock. Do not install over flexible surfaces, uncured substrates and do not omit the crack isolation membrane.

Substrate Preparation – Since any crack in a glass tile is very visible, the use of a crack isolation membrane (ANSI A118.12) over the entire surface is strongly advised. Many substrates such as mortar beds may continue to cure and shrink over a period of months, and a crack isolation membrane prevents shrinkage or movement of the substrate from transferring through to the tile. If a crack isolation membrane is not used, neither the distributor nor the manufacturer will accept any responsibility for cracking. Install only over well-cured, stable substrates. Substrates should be levelled prior to the installation of the crack isolation membrane. Do not use thin-set to level the substrate under glass tile.

Allow for a control joint wherever substrates change and as prescribed in section EJ171 of TCNA’s Handbook for Ceramic, Glass and Stone Tile Installation. (www.tileusa.com).

Installation – Confirm color, size and mounting (back or face mounted, and appropriate layout) of the entire batch of tiles before installation. Verify that sufficient tile has been ordered to complete the installation (including extra tile to make up for losses due to cutting, breakage and waste) as color matching of different batches of tile is not possible. To enhance the color of the tile, use a white thin-set mortar (ISO C2FS2P2 or 2-component, flexible, rapid cure, acrylic modified thin-set mortar system. If the tiles are dark color, use a grey thin-set to reduce the contrast. Many adhesive manufacturers such as Mapei) have tested specific products for use with glass tile (Grani Rapid and Adesilex P10). Please refer to your preferred adhesive manufacturer’s documentation for an adhesive specifically formulated for interior and exterior wall installations of glass tile. For pools and areas with frequent immersion, confirm suitability of the moisture barrier and adhesive with the thin-set manufacturer. Ensure that the leading edge where the V-cap will be installed has been ground smooth to ensure a tight install.

Important note regarding pool, hot tubs and fountain applications: Pools and other submerged applications where mosaics may be installed require that the mosaics be face-mounted with film instead of back mesh mounted. Be sure to specify that the tile will be submerged at the time of placing the order.

Spread the adhesive with a notched trowel following the manufacturer’s recommendations (in many cases a 3/16” V-notch trowel works well). Use the flat side of the trowel to flatten the ridges without removing thin-set. This step is very important to prevent trowel marks from mirroring to the surface. Use the thin-set manufacturer’s minimum recommended thickness of thin-set. Important: do not over- build the adhesive, as it may shrink and add stress or crack the glass. Spread only as much adhesive as will be covered with the tile within 15 minutes.

Thin skim coat Mosaics and other meshed assemblies may be installed directly to the thin-set adhesive. Apply the adhesive with a notched trowel and strike down the notches with the flat side of the trowel before applying the mosaic. Larger format tiles should have a thin skim coat of thin-set applied to the back of the tile to reduce voids and improve adhesion. Firmly press the glass tile against the surface to eliminate voids in the adhesive that may show through the glass tile.

Install glass tile on the wall leaving even spacing between tiles of at least 1/16” (1.5mm). Use plastic spacers whenever possible. Install control joints where the tile abuts restraining surfaces and around the perimeter of the tile work as per TCNA guidelines.

Allow the adhesive to cure according to the adhesive manufacturer’s instructions (at least 24 hours). Grout with an un-sanded grout to prevent scratching of the surface. Newer cement-free polyurethane grouts are excellent with glass tile.

Cutting – If you’ve never cut glass or you’re unconfident in your abilities, there is good news. With proper cutting tools and techniques, even beginners can learn how to produce clean, accurate glass shapes. New generation cutting tools now make sizing and shaping of glass tiles accurate and efficient with a minimal amount of breakage.

Here are a few points to ensure success as you prepare your glass tiles.

  1. Ensure you have a clean work surface to protect the glass from scratches.
  2. Have the appropriate tools.
    • Glass can be cut in straight lines, gentle curves, compound cuts. It can have both large and small holes bored into it depending on the requirements of the job. There are a range of tools from hand held scoring tools and breaking pliers up to water jet cutters. For scoring, breaking, saw cutting and boring tools we recommend montolit tiling tools. They supply a wide range of tools that will address most installation requirements.
  3. Ensure you know how to use the tools properly. A few key points to be aware of are:
    • Orient the tile so that the blade rotates into the glazed side first to minimize chipping.
    • Use plenty of water or lubricant to keep the blade or the boring tool as well as the glass tile cool. Overheating will cause thermal shock and break the tile.
    • For hand scoring tools look for a cutter with a comfortable handle and a high-quality, long-lasting wheel made of carbide steel. A 135° angle on your scoring tool is quite versatile and is appropriate for scoring glasses up to 10mm
    • When hand scoring work with your full body – stand up and away from the worktable. Keep the cutter wheel perpendicular to the glass with the handle held upright or slightly angled back toward your body. Then move your whole body–not just your arm or hand–for the most even score.
  4. Ensure your glass is at an optimal temperature.
    • When glass is cold, it can become more difficult to cut. Comfortable room temperature conditions are favorable.
  5. Score the non-glazed side of your glass tile.
    • You’ll find that scoring on the smoother surface is easier and leads to cleaner breaks.
  6. Position your score so there is an equal mass of glass on both sides of the score.
    • Otherwise, the break below the score line will naturally tend to move to the side where there is less glass, resulting in an edge that flares.
  7. Apply even pressure and uniform speed.
    • Listen for a smooth consistent sound as you score. It should not be scratchy. When scoring opalescent glasses with the correct amount of pressure, you may hear no sound at all.
  8. When cutting curves, run your score from the interior of the sheet.
    • When cutting complex shapes, start running your complex curves or circles away from the edge.
  9. Never score twice over the same path.
    • If you make a bad score, do not re-score the same line on the same side of the glass. If you must break the glass along a line you’ve scored badly, turn the glass over and very carefully score along the same line.
  10. Break your glass immediately after scoring.
    • If allowed to sit too long, a score line will begin to develop fractures radiating along its entire length.
  11. Sand cut edges and place cuts against corners where they can be covered and hidden.

Accuracy
One of the most frustrating problems can be inaccurate cutting. Here are a few tips that may help:

  1. Very often we are cutting right angles to make squares or rectangles. A simple right angle tool is very helpful with this, and several are available with a ridge to allow the tool to rest along one side of the glass.
  2. Mark where you are going to cut with a Sharpie© type marker, and making sure your cutting wheel is right on the mark.
  3. Put cork backing on your straightedge tool to prevent slippage. Cork-backed rulers, or cork tape is available at glass supply stores
  4. The Morton System consists of a line of tools that help with cutting precise angles – and some people find this very helpful.

Safety Issues

  1. You should always use eye protection when dealing with glass. Do not touch or rub your eyes while working with glass.
  2. Never hold glass by the cut edge – but rather by holding the flat surfaces.
  3. Always be aware of what will happen to the glass after it is cut – and if it is going to fall – let it, rather than trying to catch it.
  4. Always wear shoes with covered toes when working with glass.
  5. When we cut glass we want a squared off edge – but often there is an area where the glass breaks in a sharp bevel, much like the edge of a razor blade. These can be extremely sharp – and should be ground off immediately or you risk cutting yourself. If you have a triangular scrap with a very sharp point, you should grind or break that point off – or you risk stabbing yourself.
  6. Most cuts occur when reaching into the glass rack or scrap bin trying to remove a particular piece, or putting sheets of glass into the racks. Protective gloves should be worn.

Drilling – Drilling a hole requires the use of a drill bit or coring bit designed specifically for glass. Ensure that sufficient cooling water or liquid lubricant is used. If the drill and glass tile cannot be securely clamped in place, use a guide to assist alignment of the bit. A temporary guide can be made out of a scrap piece of plywood drilled with a hole slightly larger than the coring bit. Holding the guide over the desired location of the hole in the tile, slowly start drilling from the back of the tile, then complete the hole from the face of the tile to prevent glass from chipping off on the exit side of the hole. Again we highly recommend the Montolit brand for glass-specific tools.

Important – Drill holes 1/8” (3mm) larger than any anchors you plan to use. To prevent stress transfer from the fixture to the glass tile, ensure anchors are well secured to the structure (not only to the substrate) and do not allow fixtures to rest directly on the glass tile. This is particularly important in the case of frameless shower doors and hardware.

Cleaning – For routine cleaning, use any non-abrasive cleaning compound recommended for either glass or tile (such as ammonia and water, vinegar and water, etc.). Hard scale and soap residue can be safely cleaned with a mixture of baking soda and vinegar. Follow rinsing instructions carefully. A penetrating sealer may be used to facilitate clean up of cooking oils on matte finish or frosted glass.