Ceramic tile and grout, most commonly used in restrooms, locker rooms, and similar areas, can be difficult to clean and maintain. The grout is the main problem, as ceramic tile is mostly impermeable while grout is very porous. When mold and mildew removal become involved, the task can become even more difficult. It is important to know the basics of grout care to prevent buildup of mold and mildew, and also how to restore the grout back to good condition when it becomes soiled.

The first thing to think about when dealing with grouted tile is the source of mildew growth. Most often, it starts with a buildup of soils, soap scum, and skin and body oils. The mildew then begins to feed off of this contamination and grows into a problem.

Mildew growth will first show itself as a dark discoloration in the corners and edges and on the surface of the grout. If this growth is left unchecked, a slimy film can also develop on the surface of the grout. As the mildew continues to grow, an odor can become noticeable.

The longer the mildew growth exists, the more difficult mildew removal will be, and permanent discoloration can occur. It is important to remove these buildups before that can happen.

When it comes to mildew removal, there are a couple options as to how to approach it.

For small buildups:

1. Spray the area with an alkaline disinfectant cleaner, like Multi-Clean Millennium Q.
2. Allow the cleaner to dwell for 5-10 minutes.
3. Scrub with a stiff brush or counter-rotating brush machine.
4. Remove the soiled solution with a wet-dry vac.
5. Repeat the process if necessary.

For heavy buildups, when normal grout care isn’t enough, restoration of the grout is necessary:

1. Apply a deep cleaning solution, such as Multi-Clean Ultra Stripper diluted 1:8.
2. Allow the solution to dwell for 5-10 minutes.
3. Scrub with a stiff brush or counter-rotating brush machine.
4. Remove the soiled solution with a wet-dry vac.
5. Apply a brightening solution, such as Multi-Clean Double-O-Seven at 10 oz/gal.
6. Allow the solution to dwell for 5-10 minutes.
7. Scrub with a stiff brush or counter-rotating brush machine.
8. Remove the soiled solution with a wet-dry vac.
9. Rinse the floor with water and allow to dry.

Alternatively, if the grout is in good condition, pressure washing may be a viable option to deep clean grout:

1. Apply an alkaline pressure washer cleaner, such as Multi-Clean Pressure NB.
2. Allow the solution to dwell 5-10 minutes.
3. Use a pressure washer (at less than 800 PSI) to clean the surface.
4. Remove the soiled solution with a wet-dry vac.

After the grout has been cleaned or restored, a sealer can be applied to help repel soils and staining. Check out Multi-Clean’s Crete-Guard for more information.

Some general tips for mildew removal and grout care:

• Prevention is the best approach to mildew growth. Proper daily cleaning of restrooms and similar areas with grouted tile floors is the best and easiest way to prevent mildew buildups.
• Use personal protective equipment when performing cleaning tasks. In the case of grouted tile floor maintenance or mildew removal, consider gloves, goggles, anti-slip footwear, wet floor signs, and possibly a dust mask.
• If you are unsure about a cleaning product’s effectiveness, test in a small 3″x3″ area first. There is no need to waste time and product by applying a cleaner that doesn’t work over a large area.
• Do not use acid products on grout. They will deteriorate the grout and are also not nice to work with.
• Have the right tools handy. For mildew removal, this could include a stiff deck brush, a squeegee, a V-shaped grout brush, and possibly a wet-dry vac.
• When maintaining grouted tile day-to-day, use a spray and vac system over a mop and bucket system. Using a mop to clean grouted tile will leave soiled solutions to dwell in the recesses of the grout and will cause discoloration and soil buildup.

For more information on grout care and restoring grouted tile, check out our Grouted Tile Method Bulletin.

For more information on mildew removal, see our Mold & Mildew Removal Method Bulletin.

For Multi-Clean’s full line of restroom care products, visit our Restroom Care webpage.