Grout needs between 48 and 72 hours to dry before it can be properly sealed. Despite the fact that grout often looks dry within a few hours, sealing it too early can damage the grout and keep it from effectively doing its job.
Grout is the material that is used to fill in around ceramic tiles. By filling the gaps, it prevents food, dirt and water from getting between the tiles. Once the grout is sealed, it's still not ready to use. Most sealers require at least 24 hours to dry before they can get wet. Some formulas may even need up to three days to dry. Homeowners always need to consult with the manufacturer's specifications to ensure the proper installation of both grout and sealer.
Despite the fact that grout is often the go-to material for bathrooms, it still has its drawbacks. One of the biggest is that it's porous, which makes it stain easily. Sealing grout after it sets is a homeowner's best defense again staining. Sealers come in two main varieties: penetrating and membrane-forming. Penetrating sealers are preferable because they soak into both the grout and the tile. Membrane-forming sealers have a tendency to get cloudy and peel. Both types are equally resistant to moisture, but penetrating sealers usually last longer.