Sealing grout with penetrating sealer, not membrane forming sealer used in grout colorant. After the grout sealer has set, water should bead off it as though it had been waxed. If not, apply another coat of sealant. myb
Repair a crack in the grout yourself By KEITH A. PAUL Grout is construction material mainly composed of water, cement and sand, and it needs proper cleaning and sealants. A grout sealer typically is silicone- or water-based and used to protect the grout against water, dirt, mildew and other contaminants. Over time, the sealer will lose its effectiveness and should be reapplied every two to three years depending on the use of the floor.