How to Clean Porcelain Tile Before Sealing Grout
- 1). Clean the tile surface thoroughly with household cleanser diluted in hot water. Mop and rinse repeatedly until the porcelain tile surface is clean. Proceed to clean the grout while the floor is still wet.
- 2). Pour about 1/2 cup of oxygen bleach powder into a bowl. Add warm water while stirring with a small rubber spatula, to make a thick paste. It should look like cake frosting.
- 3). Scoop up some of the oxygen bleach with the spatula and spread it onto the grout lines between the tiles. Keep it on the grout as much as possible, making a thick layer. Cover all the grout lines, mixing more paste as needed.
- 4). Let the oxygen bleach sit on the lines for 30 minutes, bubbling and fizzing. Have some additional paste handy to spread onto any areas that dry up, so the whole grid of lines stays wet the whole time.
- 5). Scrub the paste into the grout with a stiff toothbrush after it's had time to work for half an hour. Rinse well. Examine the grout lines. If there are any remaining stains or discoloration, repeat the process.
- 6). Let the tile and grout dry for a full 48 hours before sealing the grout. The grout must be completely dry before sealing.
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