Most grout is made of sand and is porous, therefore things like dirt, debris, soap scum, and water get ground into the grout. All this can lead to the growth of bacteria, mold, and mildew, which is why your grout looks stained. Even if you seal your grout, that can wear down over time.
Blotchy grout colors are usually the result of too much water used somewhere during installation or cleanup process. Sometimes discoloration can occur due to minerals suspended or dissolved in the water used to mix the grout, insufficient mixing (uneven pigment distribution), or using grout that's past its shelf life.
The best way to protect your tile and grout is to regularly apply a silicone sealant. preventing water absorption and sheeting water is what it's designed to do. You apply the silicone when water fails to bead on the tile and grout.
Blotchy grout colors are usually the result of too much water used somewhere during installation or cleanup process. Sometimes discoloration can occur due to minerals suspended or dissolved in the water used to mix the grout, insufficient mixing (uneven pigment distribution), or using grout that's past its shelf life.
Steam cleaning is one of the most powerful ways to clean grout without the use of harsh chemicals. Professionals often use steam to loosen the dirt and other particles trapped in the grout without needing to scrub manually.
Grout pens will only temporarily cover your grout's discoloration. That's probably why they are the cheapest option available. We run into the infamous grout pen issue nearly every other week. The project usually goes awry when the homeowner applies the grout pen to the grout and some bleeds over onto the tile.
Hydrogen peroxide has so many uses, and it's especially good at brightening discoloured grout. Unlike vinegar, which can corrode the grout over time, hydrogen peroxide is a gentle disinfectant that is non-toxic – when used correctly. To clean grout, simply pour undiluted hydrogen peroxide into a spray bottle.
To remediate this type of problem to make the grout to be more consistent in color there are products called "grout colorants" that are epoxy based and match some of the typical grout colors. After properly preparing the existing grout joint you paint it over the joint which could be a bit tedious of a process.
Chemical cleaners, such as, Tilex, Soft Scrub, Scrubbing Bubbles, or ammonia products will nearly always result in your tile surfaces' grout becoming very discolored.
Start by combining four parts water and one part white vinegar (hint: add more vinegar to increase the cleaner's strength). Pour into a bucket or spray bottle and apply the water and vinegar mixture to the tile surface. Scrub the area using a cloth, nylon pad, or a mop.
Epoxy Grout
Epoxy grouts are the most durable of all grout choices because they are resistant to stains and water damage, and will hold up against harsh cleaners (please don't use harsh acidic cleaners on our tile!).
Why Grout Sometimes Looks Dirty When It's Clean. Sometimes, when grout is permanently stained or has an uneven appearance due to improper mixing of grout during installation, neither aggressive DIY methods nor professional cleaning will produce a completely uniform, clean appearance.
Apply Grout Cleaner
Apply it to the dirty areas of the grout following the manufacturer's instructions. If you prefer cleaning grout with a DIY mixture, make a paste of 3/4-cup baking soda, 1/4-cup hydrogen peroxide and 1 tablespoon of mild dish soap. Apply the paste to the grout with a grout brush and scrub the grout.
Make Your Grout Look New
Vinegar and Water Solution: Mix a cup of vinegar with a cup of water. Apply with a sponge or cloth to the grout. After 10 minutes, use a dry towel to wipe off any excess and let dry. Rinse with water.
The no-drip foam in OxiClean™ + Bleach Mold & Mildew Bathroom Stain Remover penetrates and breaks down tough mold and mildew stains in grout on vertical surfaces, and there's no need for endless scrubbing! Additionally, it works on vinyl curtains, sinks, counters and even no-wax floors!
Damp showers produce brown grout even more than other areas
In our showers, dampness further produces grout discoloration. Not only will our cleaning procedures contribute to the penetration of surface contaminants, but the wet environment is a breeding ground for mold and mildew.
Yes, hydrogen peroxide is a natural neutral cleaner that is safe to use on grout. Hydrogen peroxide and baking soda produce oxygenated bleach, which is highly effective for cleaning grout.
Jim Whitfield, manager of Technical Services at Mapei told industry professionals, “Because epoxy grout is so tough, it wears extremely well. It doesn't wear down over time and become a tile gutter—like cement grout can—where all the dirt and liquid and junk collects.”
You can apply new grout right over the top of the old grout. To do this, all you need is a grout removal tool. Use the tool to strike out the old grout, making sure the depth is at least 2mm, which is about the thickness of two dimes stacked one on top of the other.
After letting the cleaner sit on the grout for five minutes, we could wipe it up without any scrubbing or extra pressure. The tile looked just as clean as the untested area, with no dirt or grime in sight.