Steam cleaners are the power tools of grout cleaning (and other types of deep cleaning). They make quick work of an otherwise tedious and arm-killing job. Steam cleaners heat water to more than 200 degrees Fahrenheit and have nozzles that direct blasts of steam onto the grout. The nozzles can hold special nylon or brass brushes made specifically for grout cleaning, so you scrub while you steam. The process creates a dirty slurry of grime and water that you simply rinse or mop away.

Why Grout Gets So Dirty

Upon installation, tile grout is forced between the tiles to fill the gaps and help stabilize the tile. The surface of the tile itself is smooth and relatively easy to clean. By contrast, tile grout, being slightly lower than the tile and containing sand, attracts all sorts of debris. In tubs and showers, this gunk is mostly hardened soap scum, mineral scale, and general grime (and sometimes mold) from the moist environment. On tile flooring, the debris mainly consists of embedded dirt, but it too can contain the built-up residue of detergents.

This gunk works into the pores of the grout and, over time, becomes progressively more difficult to remove with normal cleaning. Even scrubbing vigorously with a stiff-bristled brush and using powerful cleansers and machines may produce unsatisfactory results. Steam cleaning is more effective because it uses steam and simultaneous scrubbing without the need for harsh detergents.

Choosing a Steam Cleaner

On the consumer market, there are few tools specifically made for cleaning tile grout. A general-purpose canister-style steam cleaner, heats water past the boiling point in a few minutes and maintains steam for about 30 minutes. If you want to clean the bathroom wall tile, make sure you buy a canister, multi-purpose steam cleaner. Some steamers are floor-only and will not work for shower or bathtub tile. Multi-purpose cleaners have attachments for different surfaces.

You can purchase steam cleaners or rent them at home centers and rental outlets. Most rental units are suitable for tile (and that's why most people rent them), but be sure to check with the rental store to make sure you have the right brushes for grout.

Tools and Supplies You Will Need

• Broom and mop or sponges and bucket
• Steam cleaner with grout brush attachments

Instructions

Clean the Tile

Start by cleaning the entire area where you will steam clean. This gets rid of dirt, grit, and excess gunk that will only hamper your steam-cleaning efforts. Excess dirt or soap scum also can clog the steam cleaner brush. For floor tile, sweep and damp-mop the tile. For walls, sponge-clean the tiles, using a mild detergent, if desired, then rinse.

Set Up the Steam Cleaner

Fill the steam cleaner with water, then turn on the unit and set it to steam, as directed by the manufacturer. Typically, it takes just a few minutes to create the steam. Attach the hose to the steam cleaner, as directed. Choose an appropriate brush for the size of your grout and the type of tile, following the manufacturer's recommendations. As a general rule, it's best to start with a nylon-bristle brush, which is effective on most grout and will not damage the tile. If necessary, you might move to a brass-bristle brush for stubborn dirt; just be aware that brass brushes may damage some types of tile.

Begin Steaming and Scrubbing

Turn on the steam with the recommended rate of spray. Scrub the grout directly with vigorous back-and-forth strokes. Work one small section at a time until it is clean, then move on to the next section. If you're cleaning walls, work from the top down so that all the dirty water runs down onto uncleaned areas.

Rinse and Repeat

Stop scrubbing periodically to rinse and/or mop or sponge each cleaned section. It's important to clean up the dirty water before it settles back into the grout and dries. Refill and reheat the steamer as needed, and continue the same process until the job is complete. Finish with a final cleaning of the entire area.

Sealing Cleaned Grout

Steam cleaning can be done on sealed and unsealed grout; it won't hurt the sealer. But once you've cleaned your grout and restored its original color, the best way to keep it clean is to seal it with a high-quality grout sealer. Sealers come in two basic types: penetrating and topical. Both have their pluses and minuses, so compare the options relative to your tile (including how the sealer might affect the grout color and sheen) to choose the best sealer for your needs.

Source - https://www.thespruce.com/cleaning-tile-grout-with-steam-4125933

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