Cleaning the grout found between tiles can be an arduous task, but generally the solutions are simple. For routine maintenance, or for jobs that tackle only mildly soiled or small surfaces, do-it-yourself household remedies or gentle commercial cleaners usually work well. If the surface is especially soiled or very expansive, you can clean dirty grout by enlisting the help of heavy-duty commercial cleaners.
First of all, it is important to keep a few general tips in mind before beginning any process to clean dirty grout, regardless of the size or scope of the problem. Some cleaners can cause damage to surfaces, so make sure to test a small amount of cleaning solution on a discreet section to make sure no discoloration or other warping occurs. Cleaners that contain bleach may be particularly problematic for colored tiles or grout, and should definitely be tested first. Households with small children, pets, or people with serious allergies should also consider the chemical contents of commercial cleaners before use.
Sometimes, you will be able to clean dirty grout with a simple soap and water solution, but usually these types of jobs require stronger cleaning solutions. Vinegar or baking soda diluted with water can help clean dirty grout; apply the cleaning solution to the soiled surface, let it sit for a few minutes, depending on how dirty the grout is, and then scrub with a stiff brush or sponge. If natural solutions are not strong enough, you can try using a multi-use commercial cleaning product, following the same application and cleaning process. This remedy is probably most pertinent to small surface areas such as kitchen counters or sink backsplashes.
To clean dirty grout that is either exceptionally soiled or covers an expansive area such as a floor, a different approach may be more effective. Deeply stained or filthy grout will probably be cleaned most easily by harsher chemical cleaners. Bleach-based cleaning solutions or oxygen bleach products are potent, and useful for lifting excess dirt. Before applying heavy-duty chemicals to clean dirty grout, be sure to open a window or turn on a fan to increase ventilation and reduce risk of inhaling fumes. Also, make sure to wipe down the surface with plain water or a gentle solution to get rid of any loose, easily removed dirt.
Large surface areas, such as floors, should be tackled by mopping a cleaning solution over the surface, letting it stand, and then mopping the leftover solution away with water. Grout that still will not come clean can be treated with more cleaner, and then scrubbed with a stiff brush or sponge in vigorous circular motions.