Grout sealing

What It Means

Grout sealing means applying a liquid sealer to the grout between tiles so it absorbs less water, dirt and staining. Sealers wear away with foot traffic, cleaning and the cleaners used, so the job repeats. Tile setting makers Mapei and Custom Building Products tie the timing to wear, and put it at roughly every year or two in general, with a simple water drop test to tell you when.

How It Sounds at Home

• "We should seal the grout before it stains again."
• "Do the water test, see if it soaks in."
• "The new tile needs a few days before we seal it."

The Breakdown

How often (Mapei and Custom Building Products)

Before you seal. Clean the grout and let it dry fully. Custom Building Products' data sheet for its grout sealer says the joints must be clean, dry and free of any sealer or coating already on them. Then apply the sealer exactly as its label says, including how many coats and how long to wait between them.

Make it last between sealings. Makers link sealer wear to traffic, how often a floor is cleaned and which cleaning products are used. Buhata's own suggestion: use the cleaner your sealer's label recommends, and run the water drop test each season so you reseal when it's due rather than by guesswork.

Good to Know

Every sealer and grout is different, so the product labels win over any general schedule. Wait out the grout maker's curing time before sealing new work; Mapei puts it at a minimum of 24 to 72 hours depending on the manufacturer. Follow the sealer's label, including anything it says about ventilation and gloves.

Related Terms and Categories

• Grout cleaning

  Scrubbing the lines of grout between tiles with a brush and cleaner to lift dirt, soap film and mildew stains.

• Grout vs caulk

  Grout fills the joints between tiles on one flat surface; caulk, a flexible sealant, goes where surfaces meet at an angle or can move, like a tub edge.

• Caulking

  Sealing cracks and gaps between parts of a house that don't move, such as around window and door frames, with a flexible filler called caulk.

• Bathroom deep clean

  A top-to-bottom bathroom cleaning that reaches grout, tub, toilet, floor and fixtures. The ACI's routine puts it every two weeks.

• Seasonal home maintenance

  Home upkeep sorted by time of year, so each job lands when the weather suits it and before the system it protects is needed most.

• Mildew

  A flat, usually gray or white mold that grows on damp surfaces such as shower grout, curtains and fabric left wet.

Chores, cleaning and home care