Tile Grout: Seal or No Seal?

Q:

My tile guy said that I don’t need to seal the light-colored sanded latex grout on the porcelain-tile floor in my bathroom. The handyman in the newspaper column said that I do. Who is right?

Don Pfrimmer, via email

A:

Tom Meehan, a tilesetter and the owner of Cape Cod Tileworks in Harwich, Massachusetts, replies: Apparently, the handyman did his homework, and the tile guy did not. This is a big issue in the tile industry despite the plethora of easily obtainable information. The Tile Council of North America (www.tileusa.com; 864-646-8453), The Ceramic Tile Education Foundation (www.tileschool.org; 864-222-2131), and most tile manufacturers offer technical support. When in doubt, call for answers.

At least 98% of tile and grout can be sealed. A light-colored latex-modified grout should be sealed twice because its light color is more likely to stain or become dirty than darker-colored grouts. As far as sealing the tile itself, all natural stone should be sealed, and many ceramic tiles can be sealed to make washing off the grout easier. To my knowledge, the only time that sealer hurts tile is when excess puddles are left on the tile surface. Brush or spray on sealer; then towel off the tile to remove any residue.

Using the correct sealer is also an important factor. In most cases, the sealer should be an impregnator sealer. This type of sealer is used to seal the pores of the tile or stone by penetrating the pores and blocking them from the inside to the outside. These sealers stop moisture from penetrating the surface of the tile while also allowing moisture vapor to escape the tile.

When the sealer dries, the stone or grout goes back to its dry-looking state. To make the tile shiny, you can apply an enhancer.