Grout sealant, also known as grout sealer, is a product which is designed to be applied to tile grout to protect it from hard use and the elements. This product is available from many hardware stores. Applying sealant is an important step in the grouting process which serves a number of functions. For people who have hired a contractor to install and/or grout tile, it is important to ask whether or not sealer was used.
Most grouts are porous. This means that they will absorb water, and over time, this can damage the substrate of the grout in addition to eroding the grout itself. Mildew and mold will tend to develop, and they will spread under the tile, leading to serious problems in the future. In addition, the porous nature of grout makes it a magnet for dirt and stains, and it will quickly become unsightly with use.
Grout sealant resolves both of these problems, protecting the grout and the underlayer from stains and the elements. Some sealants form a membrane over the grout, while others penetrate the grout. In both cases, when a grout sealant has been applied and it is working as it should, a drop of water on the grout should bead up, rather than sinking into the grout. Since tiles are often already sealed, the grout sealant ensures that a tiled area stays watertight. If the tiles also need sealing, a general sealant will need to be applied to the whole area.
Some grout sealants come in the form of a spray, while others are brush on. It is important that the grout be dry when sealant is applied, as otherwise, moisture will be sealed into the grout. If grout is freshly laid, people should wait two to three days before putting down sealant, remembering that the core of the grout can be damp when the outside seems dry. After the sealant has been applied and allowed to cure, it can be checked by sprinkling water on the grout to confirm that it beads.
With use, grout sealant wears down. On a high traffic floor, it may be necessary to reseal every six months or so, while other areas may stay well sealed for up to two years. When resealing, people should scrub the grout and allow it to dry fully before applying a new layer of grout sealant. Whenever new grout is laid, sealant should be the final step.
For people who do not want to have an added complication when it comes to grouting, epoxy grout can be used. Epoxy grout needs no sealant.