Tile and Grout Cleaning: What Is Safe for Porcelain, Ceramic and Natural Stone

Glazed ceramic and porcelain tile are dense and easy to clean. Unglazed porcelain and natural stone tile, such as travertine, marble, slate and limestone, are more porous, and stone reacts to acidic cleaners. Grout is usually cement-based and porous, which is why it darkens first; some newer installations use epoxy or other grouts that resist stains far better.

The Tile Council of North America suggests cleaning bathroom tile and grout weekly with a neutral cleaner made specifically for grout and tile or a mildly alkaline detergent, and keeping strong cleaners for occasional use only.

1. Remove grit first: sweep or vacuum floors before mopping.
2. Use a cleaner suited to the tile, in the dilution on the label; pH-neutral for natural stone.
3. Mop or wipe with a clean, barely wet mop or cloth, changing the water when it clouds.
4. Rinse so no cleaner film is left to attract dirt.
5. Dry showers and floors to prevent water spots and mildew.

Cement grout is porous. Soil, soap and body oils settle into it, and mopping with dirty water or too much soap leaves a film that holds more dirt. A soft nylon brush, a cleaner suited to the tile, and a thorough rinse do most of the work. Metal brushes and harsh scouring can wear grout away and scratch tile.

Two rules from the tile industry matter most. First, avoid acids: the Tile Council explains that the cement in grout dissolves in acid, so it is better to clean grout with an alkaline cleaner, and it warns against oil- or wax-based cleaners. Second, seal cement grout: the Council recommends sealing it, while epoxy grout is virtually as stain-proof as the tile itself. Its tile article suggests grout sealers may be reapplied once a year, and a major grout maker, Custom Building Products, recommends periodic testing of sealed surfaces with water and avoiding cleaners that contain ammonia, acids or bleach on sealed grout.

Grout lines that stay dark in the same place in a shower, or crumble when brushed, may be letting water behind the tile. That is a repair for a tile contractor, not a cleaning problem.

Travertine, marble and limestone tiles are calcareous stone, and they react to acids the same way a marble counter does. The Natural Stone Institute says products containing lemon, vinegar or other acids may dull or etch calcareous stones, and recommends a neutral cleaner, stone soap or a mild dishwashing detergent and warm water. Its countertop bulletin adds that vinegar should never be used on calcareous stones. On stone floors, dust-mop often: grit is abrasive.

Our granite, marble and quartz guide explains the difference between an etch and a stain, which applies to stone floors and shower walls as much as counters.

Showers combine all three problems: soap scum, hard-water film and mildew. A daily squeegee and good ventilation prevent most of it. For build-up, use a cleaner suited to the tile and grout, never an acidic one on natural stone, and rinse and dry the enclosure afterward. For mildew in grout and caulk, see our guide to bathroom mold and mildew.

1. Remove loose dirt. Sweep or vacuum tile floors; rinse shower walls with warm water.
2. Apply a neutral or mildly alkaline tile cleaner in the dilution on the label.
3. Scrub grout lines with a soft nylon brush, working in small sections.
4. Rinse with clean water. Leftover cleaner leaves a film that attracts dirt.
5. Dry. Squeegee shower walls and dry floors so water does not sit in the grout.

Change mop water as soon as it looks cloudy. Mopping with dirty water is the most common reason grout darkens again a day after it is cleaned. A second bucket of clean rinse water beside the cleaning bucket makes it easy to keep the mop clean.

Kitchen tile collects grease rather than soap scum. Wipe the backsplash behind the range weekly with warm water and a neutral or mildly alkaline cleaner; grease left for months bonds to grout and takes far more scrubbing. On kitchen floors, sweep daily in busy homes, since grit wears glazes and grout, and mop with the same gentle cleaner.

Cleaning cannot fix grout that is cracked, crumbling or missing, or grout stained deep in its pores. Those need a tile contractor to repair or regrout, and that is the moment to consider the grout type. The Tile Council notes that epoxy grout is virtually as stain proof as the tile, which makes it worth discussing for busy showers and kitchen floors. Caulk, not grout, belongs where tile meets the tub, a change of plane or a different material; if that joint is cracked, recaulk it.

For mildew on grout and caulk, see our guide to bathroom mold and mildew.

Glazed ceramic and porcelain already have a hard, finished surface. The Tile Council advises that for glazed floor tile it is not a good idea to spray anything on the tile as a coating, and it warns against oil- or wax-based cleaners on grout. Products that promise shine or a protective film tend to leave a slippery, dirt-catching layer instead. Clean glazed tile, rinse it, and dry it; that is all the finish needs.

Textured and matte porcelain, common in newer showers and on outdoor-to-indoor floors, holds dirt in its surface texture. A soft nylon brush with the same neutral or mildly alkaline cleaner gets into the texture without scratching it.

Large-format porcelain, travertine and natural stone showers are common in homes across Aledo, Hudson Oaks and the Annettas, and hard water is the usual reason shower tile looks dull. Our teams scrub tile and grout on every standard house cleaning, with pH-neutral products on natural stone; a deep cleaning adds detailed grout work and hard-water removal where possible. For a regular schedule that keeps grout from darkening, see recurring cleaning.