How to Clean Tile Grout

Illustration of products to use (and not use) when cleaning grout

 © The Spruce, 2018 

Whether it's floor tile or wall tile that's dirty with grease, soap scum, mold, or just plain dirt, cleaning grout requires two things: a grout brush and a suitable cleaner. A grout brush is a small, stiff-bristle nylon brush, available in handheld and long-handled sizes. You can substitute a toothbrush in a pinch, but its bristles are too soft to do much good. As for the cleaner, a lot of formulas work, so you can try different options to find the best performer for your tile. While there are commercial grout cleaners available, it is just as easy to do this with ingredients you already have on hand.

How Often to Clean Tile Grout

Tile grout should be cleaned whenever it becomes dirty or discolored with mold and mildew, but the frequency will depend on where the tile is located and how heavily the surface is used. Tiled wall surfaces may require this only infrequently, while tiled shower walls subject to lots of moisture and constantly humid conditions might require it weekly. The best rule of thumb: Scrub the tile grout whenever it is obviously discolored or dirty.

What You Need

It is best to try grout cleaners in the order of harshness, beginning with an alkaline cleaner, then proceeding to oxygen bleach, then chlorine bleach, as necessary.

Supplies

  • Grout brush
  • Chlorine bleach
  • Oxygen bleach
  • Alkaline cleaner
  • Safety glasses
  • Rubber gloves
  • Towel

How to Clean Tile Grout With an Alkaline Cleaner

The Tile Council of America (TCA) recommends alkaline cleaners for removing stains from grout. Alkaline cleaners include Spic n' Span, Super Washing Soda, and Mr. Clean, among many others. These cleaners are particularly good for cleaning dirty, greasy grout joints in the kitchen.

  1. Mix the Cleaner

    Mix the cleaner with water, as directed by the package label. Do not exceed the recommended amount of cleaner, as it will not improve the cleaning power of the solution.

  2. Apply the Cleaner

    Apply the cleaning solution liberally to the grout lines, using a sponge. Let the solution sit for a few minutes.

  3. Scrub the Grout Lines

    Use the grout brush to scrub vigorously at the grout lines, until stains are gone. You will notice the original color of the grout return as you scrub.

  4. Clean Away the Solution

    Sponge up excess cleaning solution, then apply fresh water. Sponge up the water to complete the rinsing.

  5. Dry the Surface

    Use a towel to dry the tile completely. Let the tile air-dry overnight before resealing the grout.

  6. The grout is now clean. Make sure to seal the grout properly before using the surface again.

How to Clean Tile Grout With Oxygen Bleach

Unlike chlorine bleach, oxygen bleach is non-toxic and safe for the environment, and it doesn’t have a harsh chemical odor. It also doesn't stain colored grout lines. Hydrogen peroxide is a form of oxygen bleach; however, it is typically sold in diluted solutions, making it a relatively ineffective cleanser for tile grout. A more appropriate product is Ajax Oxygen Bleach Cleaner or a similar product.

  1. Mix Powdered Bleach With Water

    Mix the powdered bleach with water to form a paste about the consistency of toothpaste. Normally this requires a ratio of about 2 parts powdered bleach to 1 part water.

  2. Apply the Bleach Paste

    Use a sponge to apply a coat of the bleach paste to the grout lines. Let the paste sit on the grout for 5 to 10 minutes. Make sure to use rubber gloves when handling bleach.

  3. Scrub the Grout Lines

    Now use a stiff grout brush to scrub the grout lines. You will quickly see the grout brighten to its original color.

  4. Rinse

    Rinse away the bleach with clear water, then wipe the tile down with a clean cloth. Let the tile air-dry overnight before resealing the grout.

  5. Your tile is now clean and ready for use.

How to Clean Grout With Chlorine Bleach

One traditional way to clean grout lines is using household chlorine bleach. For a full-strength application, simply dip a grout brush into a small container of bleach, scrub the grout thoroughly, then rinse with water. There are also some great grout bleach products on the market. 

  1. Wear Safety Gear

    Wear safety glasses and rubber gloves, and wear old clothes. Bleach is caustic to skin and can bleed the color out of clothing.

  2. Ventilate the Space

    Open up windows to ventilate the area. Bleach is toxic and releases noxious fumes. In a bathroom, running the vent fan at the same time you open the windows provides excellent ventilation.

  3. Scrub the Grout Lines

    Dip the grout brush into the pure bleach, apply it to the grout lines, and scrub vigorously to remove stains.

  4. Rinse

    Rinse the tile thoroughly with clear water and sponge it up to remove the bleach. Repeat. It is critical that all bleach be removed before you move on to resealing.

  5. Dry the Surfaces

    Dry the tile surface with a clean, dry towel. Let the tile air-dry overnight before resealing the grout lines.

  6. Ordinary household chlorine bleach is an effective way to clean grout, but because you are using it full strength, caution is required when using it.

Avoid Vinegar or Baking Soda

Alkaline cleaners are a better choice than vinegar or baking soda because grout contains cementitious mortar that can be dissolved by acidic cleaners, including vinegar. Don't use any vinegar or acid-based commercial cleaners on grout.

Vinegar and other acids are also a bad idea for stone tile because the acid can etch the stone. Another widely praised household cleaner, baking soda, is alkaline (not acid), but it is not very effective as a grout cleaner.

Sealing the Grout Lines

Cleaning grout lines can be a difficult and physical process. Once you have the grout looking clean and stain-free, sealing the grout will create a protective surface that helps prevent future staining and makes it much easier to keep grout clean. It's important to follow the manufacturer's instructions carefully when applying grout sealer. The tile must be clean and completely dry, and you must let the sealer cure fully before using the tiled area.