#MAPEITechTip: Glass Tile -a little ‘bling’ goes a long way to give a custom look to a project

Today in our 21st Century Glass Mosaic Tile is finding a new generation of admirers as building owners and homeowners are looking to make use of various finishes now available, including glass mosaics and tiles, that are not only functional but often a work of art. Glass tiles popularity can be attributed to a Large Variety of colors that are available in opaque & clear that reflects natural and indoor light.  Imperviousness to water, staining opaque or clear and now larger in sizes than previously available (see the ANSI Handbook A137.2 “Specifications for Glass Tile” which defines various types, sizes and physical properties for glass tile). 

Glass tiles were used in mosaics as early as 2500 B.C., and by the 3rd Century B.C. artisans in Greece, Persia and India began forming glass into tiles.  A story began to circulate in the Roman Empire during the reign of Emperor Tiberius (14-37 AD). By the 8th century the Venetian’s were already expert glass makers. The conquest of Constantinople in 1204 C.E. further expanded their knowledge of glass making techniques.  The Venetian’s began incorporating all these various techniques from the Eastern Mediterranean and Islamic Territories.  In a ploy to guard their new-found secrets the “Artigiani” were relegated to the Island of Murano, Venice. In 1859 a lawyer named Antonio Salviati came to Murano Italy to establish a new business…producing glass mosaic tiles for repairing Venice’s decaying buildings and setting the industry sight to future Architectural Projects.
 

Glass tile is really that accessory that takes a project to the next level to give it that customized look in both residential and commercial spaces, but there are limitations to where it can be used. Always consult the glass tile manufacturer’s recommendations for acceptable installation applications such as backsplashes, bathrooms, showers, living room or lobby feature walls, exterior facades and water features, such as pools and fountains (check with the tile manufacturer, some glass tiles use a mesh backing adhered with an adhesive that can dissolve in submerged applications). Similar to Porcelain tile (low porosity) glass has little to no texture or porosity to allow the adhesive to "Grab" the back of the tile and bond it to the substrate both chemically and mechanically. This poses challenges for both the installer and the adhesive manufacturer.  Add to this the fact that many sub-floors that are now acceptable for tile and stone may not be suitable for setting glass tile. The clearer the glass (opacity) the more important it is to have an adhesive that is ultra-white to enhance not dull the glass tile.

Specialty Adhesives must be used to address this issue. These adhesives must also handle varying movements between the glass tile and substrate, known as thermal growth, when installed on exterior applications or water features. Due to glass’ sensitivity to thermal growth and shock, in addition to a high-performance mortar, these types of installations require the placement of movement joints (TCNA EJ-171; use an appropriate elastomeric sealant like MAPEI Mapesil T or Mapesil 3D) to accommodate varying movement within the glass installation.  MAPEI’s Adesilex P10 with water is great for backsplashes and all dry to wet applications, when you get into the water features where the application will be submerged (greater exposure to thermal growth/shock), use the Keraply latex additive in place of the water.  What makes Adesilex P10 such as superior mortar for translucent or opaque glass tile, it is formulated as a ‘bright white’ mortar. This maximizes the ability of the mortar to allow the glass tile to be the ‘star’ without influencing the brilliance.  The Installer must ensure that the surface is flat and plumb, prior to spreading the mortar so as to eliminate any "air pockets" or "voids" that will be visible through the clear glass. Unlike ceramic or porcelain tile that is placed into the mortar with combed ridges, when installing glass tile, there should not be any ridges that can telegraph through and effect the look of your glass.  It is always a good practice to flat trowel your mortar.
 

What about the grout, does it really matter which type of grout you select?  Using the wrong grout can cause your glass tile to look dull, lackluster or flat, conversely using the proper grout will take it to the next level, making it pop.  Does your glass installation include a water feature, typically a cement-based or epoxy-based grout will be the perfect choice for these more challenging submerged application.  MAPEI’s Ultracolor Plus FA grout, which uses calcium aluminate technology in place of Portland-cement-based cement, eliminating concerns with 'efflorescence' and damage to your glass tile investment. 
 
Are you looking for some additional bling to your project? If so, Flexcolor 3D is the perfect complement to glass tile, it is a ready-to-use (RTU) grout.  It is translucent, allowing light pass through it, highlighting the colors of the tiles around it.  Because it's part of the Flexcolor family of grouts, it is based on acrylic technology that eliminates the need to mix multiple components together and is ready to use right out of the bucket.  It is also easy to clean and stain resistant.  Just keep in mind, this product is not intended for submerged applications, but is well suited for intermittent wet applications.
 
Following some of these simple reminders will ensure the glass tile will shine and sparkle for years to come!