The problem with grout it is that it is easily stained, and because it is rough and porous, it can be difficult to clean. Whether your discolored grout is in your shower, countertops, or floors, the following tips will help you keep your grout looking its best.
Cleaning white grout
To clean white grout, apply a mixture of bleach and water, or better yet, use a bleach pen or grout pen. By using a bleach-gel product, you can allow the bleach to stay on the grout for a while, giving it time to do its work. A bleach-gel toilet cleaner will be more cost-effective than a small pen if you have a lot of grout to clean. Using bleach around some types of specialty stone is inadvisable, so try a solution of vinegar and water instead. Check with the tile manufacturer or test an inconspicuous area for color fastness.
Once you've done a preliminary cleaning with bleach, mix up a homemade paste of baking soda and hydrogen peroxide, and scrub with an old toothbrush, grout brush or other narrow bristle brush. When you are done, wipe the grout to remove any residue.
What about grout that isn't white?
If your grout isn't white, you may not want to risk using regular bleach. Try removing smaller stains with a Clorox Magic Eraser® or even a pencil eraser. For cleaning larger areas of grout, an "oxygen bleach powder" may be the answer. Stain Solver® is one such product that claims to be gentler on colored surfaces than regular bleach products, and the buzz online is that it works for cleaning grout.
Commercial grout-care products
When household cleaning products and stain removers are not effective in cleaning your grout, it may be time to bring in the heavy artillery. Grout Renew® and Grout Refresh® are grout restoration products, which come in a variety of colors. These products are applied with the same type of narrow brush used to clean grout. Keep paper towels handy for wiping any mistakes off the tile as you go. After you have successfully improved the look of your grout with a color-specific restoration product, you may want to apply a grout sealant to help prevent staining. Grout stains, sealants and a variety of specialized grout products are available at Lowe's® and other home improvement stores.
Preventing grout problems
To prevent future grout headaches, ask your contractor to use a dark-colored grout when putting in new tile, especially for flooring. Consider using a grout stain to darken the color of your existing grout to more closely match the color of, well…DIRT. Creating a schedule for cleaning your grout more regularly can prevent permanent staining. Hiring a grout specialist to professionally clean and seal your grout is also an option.
With the right tools and products, and a little bit of elbow grease, you'll have unsightly grout looking better in no time. As a last resort, you can replace severely-damaged grout, but you will need to purchase a grout saw, and it is probably best to call a contractor or a tile and grout specialist.