How to Clean Grout on Tile Floors

No matter how often you wash your tile floor, it's not really clean unless you are also taking care of the grout. Those tight, little lines of rough, porous surface are magnets for dust and germs, and once your grout has discolored, it can make the entire floor look old and dull. You'll find many suggestions for homemade tile grout cleaner, but most of them aren't strong enough to tackle the particular challenges of cleaning grout. The best way to clean grout is often a commercial grout cleaner and, for particularly stubborn dirt, a grout steamer.

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You need to clean the grout if you truly want a clean floor.

Facts About Grout

Grout fills in the spaces between the tiles to protect the edges and help keep the tiles in place. It comes in many different types, but the three most common are unsanded, sanded and epoxy. Grout is made up of cement,usually Portland cement, an aggregate and water.

Unsanded grout is used most often when the space between tiles is less than 1/8 inch wide. It sticks better to vertical surfaces and is often used on marble, where flecks of sand could scratch the surface of the tile as the grout is applied. Sanded grout contains silica sand and is most often used for tiles that are set farther apart than 1/8 inch. It has a coarser texture than unsanded grout. Epoxy grout is used mostly by professionals in situations where the tile may be exposed to acids or oils that could interfere with the adhesion of sanded or unsanded grout.

Homemade Grout Cleaner

Homemade grout cleaner containing vinegar isn't ideal for grout. Vinegar is acidic and can break down the grout. Baking soda is alkaline, but it isn't powerful enough on its own to be an effective tile grout cleaner, and mixing it with vinegar doesn't have enough effect on its acidity to make it safe. Hydrogen peroxide is usually so diluted that it's not strong enough to clean grout. Bleach is strong enough, but it's also toxic and releases harsh fumes.

Best Way to Clean Grout by Hand

Commercial grout cleaners, grout bleach, alkaline floor cleaner and oxygen bleach are options for cleaning your grout lines. For mildly soiled grout, mix the powder into a bucket of warm water and apply it to the grout lines using a sponge or cloth. Let it sit for 15 minutes and scrub with a grout brush to remove any remaining stains. Mop it up, paying special attention to the grout. Rinse with clear water and use towels, shop cloths or a wet/dry vacuum to remove any remaining water.

For very old or deeply soiled grout, mix the powdered oxygen bleach with warm water into a thick paste and then apply the paste to the grout. Oxygen bleach is nontoxic and has no harsh fumes, so you can apply it with an old toothbrush or put on dish-washing gloves and apply it with your fingers. Let the paste sit for five to 10 minutes and then scrub it with a grout brush.

Wear knee pads or kneel on a folded towel to help protect your knees from the hard tile. Rinse the floor by mopping it with clear water. This may not get all of the oxygen paste bleach off of the floor, so go over it thoroughly with a clean, lint-free cloth dampened in clear water. Wring or rinse the cloth frequently as you work.

Using a Grout-Cleaning Machine

Steam cleaners use pressurized steam to clean tile and grout. Read the instructions carefully before adding any sort of cleanser to the water to avoid damaging the machine. Follow the manufacturer's instructions for filling and starting the machine, and then simply move the steam cleaner's wand slowly over the floor the same way you would use a vacuum cleaner on carpet. Pay special attention to high-traffic areas. Let the floor dry completely before walking on it.


Brynne Chandler

Brynne Chandler

Brynne Chandler built her first bookcase at eight years old, which is also right around the time she started writing. An avid crafter, decorator and do-it-yourselfer, Brynne has remodeled several homes including one cantilevered on a cliff and one that belonged to Olympic swimmer and actor Buster Crabbe. Best known for her EMMY-nominated TV animation writing, she has been writing non-fiction content for almost a decade and has been featured in the San Francisco Chronicle and the Houston Chronicle online, among other places.