Glass tiles may be installed on interior or exterior wall areas, in wet or dry locations and in hot and cold climates. They can be used for wall installations and light duty floor use (showers, accents). In general, glass tiles differ from ceramic tile products, so extra caution and attention to installation instructions is recommended. Glass tile should not be exposed to high abrasion, high impact and thermal shock or installed over flexible surfaces.

Important – since any crack in glass tile is very visible the use of a crack suppression membrane is recommended. Many substrates may continue to cure and shrink over a period of months, and a crack suppression membrane prevents shrinkage or movement of the substrate to mirror through the tile. If a crack suppression membrane is not used, neither the distributor nor the manufacturer will accept any responsibility should any cracking occur.

Install over well-cured stable substrates. Allow for an expansion joint whenever substrates change (see below).

Installation – Use a white thin-set mortar 2 component, flexible acrylic thin-set mortar system, formulated for interior and exterior wall installations.

Use any of these acceptable setting systems.

• Custom Building Products – Premium Plus Thin-Set Mortar (white) mixed with Custom Flex Ultra-Strength Thin Set additive.
• Custom Building Products – Megaflex Ultimate Thin Set Mortar (white). No admixture necessary.
• Custom Building Products – Megalite Crack Prevention Mortar (white). No admixture necessary.
• Kerakoll – H40 Tenax Single Component Thin-Set (white). No admixture necessary.
• Laticrete – 254 Platinum Multipurpose Thin-set Mortar. No admixture necessary.
• Mapei – Kerabond Premium Dry-Set Mortar (KER 102) mixed with Keralastic Mortar Admixture (KER 310)
• TEC – Super Flex Premium Performance Universal Latex- Modified Thin-Set Mortar. No admixture necessary.

Spread the adhesive with a notched trowel, following the manufacturer’s recommendations (in many cases a 3/16 X 3/16” v-notch trowel will work). Do not overbuild the adhesive as it may shrink and add stress to the glass. Spread only as much adhesive as will be covered with tile in 15 minutes. Longer exposure will result in the thin set developing a “skin coat” and will not be as effective. Always “back-butter” each piece of glass with the flat edge of the trowel to provide a void-free installation and good contact with the mortar bed. Carefully press the glass against the wall to prevent the notch marks in the adhesive from showing through the glass. Allow the adhesive to cure according to the manufacturer’s instructions (at least 24 hours).

Install control joints where the tile abuts restraining surfaces and around the perimeter of the tile work. Expansion joints are essential for the success of most tile installations. Follow the instructions on Expansion Joints in the Handbook for Ceramic Tile Installation (published by the Tile Council of America) section EJ 171-05.

Expansion Joints – Since glass tile features a higher expansion/contraction coefficient compared to ceramics, you need to provide some room for the movement within your installation (a soft joint). These soft joints should be installed at all changes of plane where the tile meets a dissimilar material. It is especially true for areas of temperature changes. To address the issue, a flexible sealant (caulking) should be applied.

Pools – When glass mosaic is installed in pools and other wet areas, it is required to arrange expansion joints within the waterline and at its top, as well as at corners and raised areas where tiles border on other materials. The joints should be located every 8-12 feet and has to comply with TCA method EJ 171. Also, it is very important to use the sealant/caulking in areas adjacent to the coping/decking. Though this standard requirement for outdoor installations is often neglected in ceramic tile projects, it is critical to follow the recommendation when it comes to glass tile.

Liners/Quarter Rounds – Do not build up thinset in the voids behind the dome liners or quarter rounds. It may shrink and stress/crack the glass as it dries.

Grouting – Grout with either a sanded or an non-sanded grout. When grouting glass tiles with smaller grout joints we recommend a non-sanded grout. If using sanded grout mix the grout to a “watery” consistency to avoid scratching the surface of the tile.

Cutting – Glass tile is best cut using a wet saw with a special diamond glass-cutting blade. A blade for cutting glass has a smaller diamonds then a tile blade, has a continuous rim and runs at a slower speed. Note: A blade designed for cutting ceramic tile is course and will chip the glass. Whenever possible cut edges should be sanded and placed in corners where they can be covered or hidden. Note: straight cuts generally do not result in additional stress to the glass tile but notched cuts may add stress and cause cracking of the glass. Keep in mind that in many cases it may be easier and less expensive to mark your cuts and take the tile to a professional glass shop for cutting or drilling.

Cutting Curves/Holes – Drilling a hole requires the use of a drill bit or coring drill that is designed for glass. If the drill and glass tile are not securely clamped in place, drill a small hole through the glass to act as guide. Always use a proper glass drilling bit, keep the drill bit and hole lubricated with turpentine or water and drill at very slow speed. Start drilling from the back of the tile, and then complete the hole by drilling from the face of the tile. Attempting to drill all the way through the tile from one side will cause glass to chip off on the exit side of the hole. Important: Drill 1/8’ larger than any anchors you plan to use. This will 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.

Cleaning – For routine cleaning, any nonabrasive cleaning compound (such as aqua mix concentrated tile cleaner, ammonia mixed with water, vinegar mixed with water, etc) that is recommended for either glass or tile can be used. Do not use colored cleaners (Windex) as the color may discolor the grout. Follow rinsing instructions carefully.