Nothing says luxury and elegance like glass mosaic tile. The tiny pieces are often translucent, blanketing a pool with an ethereal glow that’s utterly unique in aquascape design.
However, the effect is only as good as the installer who creates it. Working with this type of tile requires experience, expertise, and attention to detail. Some brands are manufactured in sheets with paper facing, making them difficult to maneuver because the front isn’t visible during installation. Other tiles are created with a beveled perimeter on the back, which reduces the amount of surface area that can make solid contact with the thinset.
Improper installation can result in a shoddy-looking project. Worse, if not carefully applied, the tiles will pop out, creating an embarrassing—and expensive—eyesore. To help prevent this, ANSI and the Tile Council of North America recently published standards specifically addressing glass mosaic tile.
“There are misunderstandings and a lack of common ground for the approach to working with these materials,” says Scott Fleming, who authored the standards and works as director of technical services for Oceanside Glass Tile in Carlsbad, Calif. “We saw some failures that really would have been easily avoided. And when we see failures, they’re not almost-misses—they’re way off track.”
The standards cover three methods for installing glass mosaic tile:
The wet-set method: This traditional technique, now rarely used, involves placing the tiles onto a wet mortar bed with a coat of pure cement on it, rather than thinset. Installers spread a thin layer of grout on the back of the sheet, in a process called back buttering. Then the tile is tapped into place.
Alternate method: With this more common technique, installers wait for the mortar bed to cure, then apply thinset. They back butter the sheets of tile and tap them in place, as with the wet-set method.
Direct-bond method: Here, tile setters apply the sheets directly onto the thinset without back buttering. They return later to grout.
Drawing from these standards as well as personal experience and observations, Fleming and master tiler Greg Andrews of Andrews Tile in Agoura Hills, Calif., examine the six most common mistakes installers make with this precious product and how to prevent them:
To make the process easier, Andrews will sometimes create a life-size template of the problem area, such as a step, then figure out exactly how to lay the tiles. An especially tricky spot might even require him to cut sheets up row by row, then remount the strips to form a new sheet that will fit the special contour. He brings the handmade sheets to the site, and installs them like any other.
One recent project involved a curved pool with a large medallion on the floor. It seemed simple—just place the circular adornment in the center. But the tricky part was how to set the tiles around it, and how to make the transition to the walls. Andrews bordered the floor’s perimeter with a contrasting line two tiles thick. This served as a barrier. The background tiles were placed in a circle to radiate around the medallion until they reached the floor’s outline. Everything behind that line and up the walls was installed in a simple bond pattern.
In general, Andrews prefers the alternate method. “It gives me the ability to manipulate tiles and negotiate curvatures and corners,” he says. “I could do a tremendous amount of work with that type of method because I don’t have the fear of the thinset coming up through the tile.” However, he’ll make an exception for vanishing-edge walls and other areas that experience wet and dry conditions or temperature extremes. To help prevent delamination problems, he’ll use the direct-bond method, which tests have shown to be stronger. However, Fleming cautions that the tests only monitored new installations and did not indicate long-term performance.
While rarely used, the wet-set method can be practical in areas that experience extreme climates, since many modern thinsets only perform reliably in temperatures between 40 and 90 degrees F.
Tile designer: Opio America, North Hollywood, Calif.; Tile installer: Andrews Tile, Agoura Hills, Calif.
Tile installer: Andrews Tile
