After you install glass tiles, you may notice a cloudy, semi-white or yellowish haze on the tile. The haze forms when the grout residue hasn't been completely cleaned from the surface, and it often remains if you clean it. The best time to clean the haze is soon as you install the tiles, but you still should be able to remove the haze even weeks following installation by using these methods.

Prepare to Clean the Haze

To remove the haze, you need:

• work gloves
• sponge
• bucket
• putty knife
• cheesecloth
• soft nylon brush
• small mop (optional)
• terrycloth towels
• white vinegar
• grout haze remover that contains phosphoric acid
• glass tile cleaner

Grout is either cement, ready-mix, or epoxy. Cement and ready-mix can easily be cleaned with home cleaners, but epoxy requires professional tile cleaning services to avoid tile damage.

If you just recently installed tiles, let the grout set for a day to make removal easier and to avoid dislodging the grout. Avoid using standard household cleaners, as they aren't strong enough to clean the haze. 

Clean with a Cheesecloth or Nylon Brush

Try removing small patches of grout haze with non-abrasive methods first to minimize glass damage. Rub the haze with a cheesecloth, which is available at hardware stores, shaking the cloth as needed to dislodge dust. Remove loosened grout with a sponge, and use a putty knife to smooth additional grout.

Alternately, try a damp terrycloth towel, and wring it as needed. You may also use one towel to dampen the grout and another towel to wipe it. If the towel or cheesecloth don't remove the film, clean it with a nylon brush dampened in warm water.

Apply White Vinegar

Proceed to use vinegar if scrubbing doesn't remove the grout haze. Test the cleaner on a hidden spot to check for a reaction. 

Combine one cup of white vinegar with a gallon of warm water in a bucket, and shake to blend. Dip the nylon bristle brush or small mop in the solution, and rub the grout haze.

Rinse the solution using clean water followed by a glass tile cleaner. Don't use a vinegar solution too often on grout, since the mixture can soften it.

Use a Grout Cleaner

If all else fails to remove the haze, apply a commercial grout cleaner, but be certain to buy a remover that contains phosphoric acid. This cleaner won't damage glass.

Dab some cleaner on the mop or scrub brush, work it in the spot, then rinse with clean water. Don't apply grout remover to colored grout, since it has bleach.