Sealing Tile Grout: Methods To Keep Tile Clean and Maintained

Kitchen tile
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Sealing tile grout may seem like a thankless job. Then you consider the problems that can erupt from not doing this:  stained grout that is impossible to clean, plus insidious mold and mildew.

Compared to scrubbing your tile with a toothbrush, applying grout sealer begins to sound pretty good.  There are two methods, one more effective than the other:

1.  Seal Grout Lines Individually With Applicator (Preferred)

Basics:  Brushing each grout line with sealer.

You May Like Because:  Coats the grout thickly.  Also, very little sealer remains on tile surface.

Best Products:  Though pricey, DuPont's Grout Sealer effectively seals your grout lines, each 4 oz. bottle covering 30 linear feet.  Brush tips tend to work better than foam roller tips.


The surface of ceramic tile is glazed, meaning that it is already sealed. Tile grout sealer needs to be applied only to the grout lines, and nothing else.  This is why this method works best:  though more manual labor is involved, you target the sealer only on the section that needs it--grout.

This type of grout sealer usually comes with an attached brush-tip or roller-tip.  Gardening knee pads or a folded up towel help protect your knees as you crouch down to apply the sealant to each line.

If you smear some on the surface of the tile, it will eventually come off.  But you do want to try your best to keep it away from the tile surface.

Tile grout sealing should be done roughly once a year.

2.  Seal Grout By Spraying Entire Tile Surface (Alternate)

Basics:  Spray the tile--surface, grout, and all--with a grout sealer.

You May Like Because:  It it far easier to spray everything instead of "drawing" grout lines individually.  Ease of use may encourage homeowners to seal their grout more often.

Best Products:  While some purchasers may not like the word "aerosol," the push-button aerosol sprays tend to produce a finer, more consistent mist with less drips than do the hand pump sprays.  


A second method involves spraying the entire tile surface (as long as the surface is glazed). The theory is that the grout sealer penetrates the porous grout, as it should, yet lays atop the glazed tile surface. Then, the sealer on the glazed tile partially evaporates and partially wears off after usage.

Reviews of spray on grout sealant are mixed. Some homeowners say that this spray-on sealant does not percolate into the grout as well as the brush-on sealers. Also, there are some reports of this sealant damaging the tile caulk—not a good thing.

Understand What Grout Is About

After you have laid tile in its bed of mortar and let it harden, grout comes next.

Grout, either natural or color-tinted, is smeared onto the face of the tile and forced into the tile seams with a rubber float.


Grout keeps debris out of the seams and it acts like a glue that holds the tile edges together.  If you chose color-tinted grout, it is more than just functional--it adds to the beauty of the tile.

What Grout Sealer Does For Your Tile

Tile is so multi-purpose, it can be used anywhere: kitchen, bathroom floor, kitchen backsplash, even inside the shower. Depending on the location, tile might get zero or very little moisture or it can be absolutely deluged with moisture, in the case of a tiled shower.

Because cement-based grout is porous, those pores allow water to percolate inside.  Epoxy-based grout is different and is not covered in this article because it does not need sealing.

By applying sealer, you are, in effect, beating water to the punch.  You are flooding, permeating, and completely occupying this porous grout structure with a stable, hard substance--grout sealer--before the water can move in.

Few tile installations do not need grout sealing.  The portions of a kitchen backsplash extending past the sink which do not receive water splashes can be left unsealed.  Any kind of tile that is purely decorative like wall medallions or dry tile wall wainscot can go without sealing.