Layout: “The surface should be perfect for mosaic tile, freshly skim-coated and perfectly plumb,” says New York–based tile contractor Joe Cangialosi. “Glass mosaic should be laid out dry first, to see where the sheets come together and to avoid visible cuts.” To cut glass mosaics, use a glass-tile nipper ($13; The Home Depot) or a wet saw for the cleanest line.
Anti-fracture membrane: As a room settles, shifting can cause any tiles to crack; in addition, glass expands and contracts more than other types of tile, and mosaics have more grout lines. So it’s key to install an anti-fracture membrane—mesh sandwiched between two layers of a rubbery waterproof compound—before applying a bed of thinset for the tile.
Connective material: Mesh is the most common, joining tiles in back to form sheets about 12 inches square for quicker installation and easier, more accurate adjustments. Paper facing is used for some transparent glass tiles, so there is no backing that shows through once the tile is installed.
Thinset, grout, etc.: Pick one brand of setting materials and use the entire system so you are covered by the company’s warranties. If your tile lacks an opaque coating in back—a superthin layer baked on during manufacturing—use white thinset and smooth the trowel marks before installing the mosaic sheets, so no gaps are visible.
Shown: After thinset is troweled on, place the mosaic sheets along the surface. Slightly rock the sheet up and down to help the tile settle into place.
Removing a Paper Facing
To remove a paper facing, blot it with a wet sponge several times; wait 5 to 10 minutes. Once the paper is saturated, peel it off at an angle, starting from an upper corner. Watch a step-by-step video on How to Install a Glass Mosaic Tile Backsplash.
Care and Maintenance
Though the upkeep is easy, give glass mosaic tile regular attention to keep it sparkling.
Cleaning: Use a soft, lint-free cloth and a nonabrasive cleaner to keep glass gleaming. With cementitious grout, avoid acid-based cleansers, including distilled white vinegar, which can weaken it. In areas like the shower, mineral buildup may necessitate more frequent cleaning.
Sealing: Use a Teflon grout sealant on cementitious grout after installation, as soon as it’s dry, to protect it from water and stains. You will still need to stay on top of spills and spatters, like tomato sauce on a backsplash, and wipe them up before they have a chance to seep in. If you choose a glass-and-stone blend, ask if the stone is presealed, or if you need to take care of that after installation, then reseal periodically.
Repairs: As with any tile, if it gets cracked or broken, you can tape off and remove the damaged pieces and setting materials to patch in new tile. Keep a carton of extra mosaic sheets on hand to ensure that the replacements match perfectly. This is especially crucial if the repair involves plumbing behind the tile surface and requires removing and then replacing several square feet of mosaic.