How to Lighten Old Tile Grout
- 1). Mix 1/2 cup baking soda, 1/3 cup ammonia, 1/4 cup vinegar and 7 cups warm water into a spray bottle and shake well.
- 2). Spray the mixture on the old grout and allow it to sit for 2 to 5 minutes. Wipe the grout off with a damp cloth.
- 3). Mix ¼ cup hydrogen peroxide, 1 cup salt and 1 cup baking soda into a paste. Apply it on the old grout with the grout brush. Scrub the mixture into the grout until the grout starts to lighten. Rinse the mixture off with water.
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