- 1). Apply one coat of high-quality penetrating grout and tile sealer to the sandstone patio tiles before installing them. This will make the grouting process easier and will prevent the dyes in the grout from seeping into the sandstone tiles.
- 2). Allow the grout to dry and cure for at least 72 hours before applying the sealer to the patio tiles. If the grout has not had enough time to cure, the sealer will not penetrate into the grout and dry correctly.
- 3). Apply penetrating grout and tile sealer by either spraying it directly onto the tile or spread it with a sponge (either a grout sponge or a small kitchen sponge will do the trick).
- 4). Allow the sealer to dry for two to three hours between coats. Apply two to four total coats of sealer to the sandstone patio pavers.
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