How to stop bathroom grout from going black?

Author: Juston Fadel  |  Last update: Wednesday, July 30, 2025

To comprehensively prevent mold growth on grout, it's important to combine grout sealer with proper bathroom or shower maintenance practices. This includes adequate ventilation, regular cleaning to remove organic matter that mold feeds on, prompt repair of leaks, and the use of mold-resistant products where applicable.

Why does my grout keep going black?

Grout will darken when it absorbs water. Even if the grout is sealed, a small bit of water may pool in some areas causing the grout in that area to appear darker on a regular basis. Squeegee the shower after using, otherwise you'll have to pull and replace tile to fix any low spots on the shower floor.

What does it mean when grout turns black?

The dark spots on grout are most likely the result of mold, mildew or plain old dirt buildup. It is important to determine what you're dealing with first, so you can wipe it out with the appropriate treatment plan. The only way to tell for sure is to ask a mold professional to collect samples and test it.

How do I keep my bathroom grout white?

To help you out, here are five simple ways for cleaning grout and keeping them stain-free:
  1. Regularly Clean Your Grout With A Bleach-Free Cleaner.
  2. Vacuum Or Sweep Your Floor Regularly.
  3. Wipe Up Spills Immediately.
  4. Use A Sealant To Protect Your Tile Grout.
  5. Avoid Using Harsh Chemicals.
  6. How Do You Naturally Get Out Grout Stains?

How do you get rid of black mold in grout?

Vinegar Soak: Create a potent mildew-fighting solution by soaking a cloth or sponge in undiluted white vinegar. Place the saturated cloth over the moldy grout and let it sit for several hours or overnight. The acidic nature of vinegar helps break down mildew, making it easier to scrub away.

Amazing Method! Even 50 Year Old Tiler Never Seen Such Method

How do you keep grout from turning black?

If you can get on a regular cleaning schedule to scrub the grout and tile, you'll be ahead of the game in stopping black mold from forming in the first place.

Is bleach bad for grout?

The long-term use of bleach on grout can lead to several adverse effects. As an oxidizing agent, bleach can weaken the cement binding the grout, reducing its durability. Additionally, it can cause discoloration, leading to an uneven and blotchy appearance.

How do you keep mold out of bathroom grout?

Mold thrives in moist areas, so it's no wonder your bathroom is an easy spot for it to appear. Leave your shower door or curtain open after a shower to give the space a greater opportunity to dry out. You can also use a squeegee to really get rid of the water. Seal your grout.

Does sealing grout keep it white?

The other condition that can cause grout to turn white or cloudy is if water is trapped under the tile and the grout is sealed with a non-breathing sealer. If this is the case then you have to remove the sealer if it is a surface sealer. If the sealer is deep into the grout then you might have to replace the grout.

How do professionals clean grout?

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.

How to get rid of black mold in shower?

Solution: Baking Soda

It kills black mold and absorbs moisture that attracts mold. Combine ½ cup of baking soda with just enough water to make a paste. Apply the paste to the affected area and let it dry. Use a soft bristle brush to remove the dried paste.

Why do tilers hate black grout?

It's important to remember that black grout can be very messy and difficult to clean up. Grout is similar to kinetic sand in texture—it's gritty, and it can go everywhere, even with the most experienced professional. And because there's such a contrast between the tile and grout color-wise, any mistake will stand out.

How do you change black grout to white?

How to Change Grout Color With a Colorant
  1. Scrub the Grout Lines. Use a commercial grout cleaner to thoroughly scrub the grout lines with a small stiff scrub brush. ...
  2. Test the Colorant. ...
  3. Clean and Rinse the Tile and Grout. ...
  4. Mask Off the Tile Surfaces (Optional) ...
  5. Apply Colorant. ...
  6. Wipe Off Excess Colorant. ...
  7. Seal, if Necessary.

Does grout haze remover work on mortar?

A pre-mixed, ready-to-use, mild acid solution. Removes dried Portland cement grout haze and mortar residue from tile, concrete and masonry.

How to stop grout from going black?

Now your mould is gone how can you prevent it returning?
  1. Keep your bathroom or affected area well ventilated; keep windows open or your extractor fan on for 20 minutes after a shower or bath.
  2. Hang bath towels to dry after use.
  3. Apply mould preventing solutions as above regularly.
  4. Keep your tiles clean.
  5. Seal your grout.

What grout sealer is best for showers?

To seal to perfection, we recommend using Universeal Grout and Tile Protector. This product is a solvent based sealer designed to deeply penetrate your grout. It is effective in preventing stains from oil and water-based liquids and it will not discolour your tiles.

What kills black mold in grout?

Mix one part bleach with three parts warm water in a spray bottle. Make sure you're in a well-ventilated space (turn on the fan to help air circulation) and have your gloves on. Spray the mixture on the mold-infested areas and leave it for an hour.

What should you not use to clean grout?

Chemical cleaners, such as, Tilex, Soft Scrub, Scrubbing Bubbles, or ammonia products will nearly always result in your tile surfaces' grout becoming very discolored.

How to clean white grout that has turned black?

As a cleaning paste, mix 1/2 cup baking soda with 1/4 cup hydrogen peroxide. You can recycle a squeeze bottle with a nozzle for easier application! Spread the paste over the grout and let it sit for at least 5 minutes. Then use a stiff-bristled brush to scrub the grout until it's clean.

Is OxiClean a good grout cleaner?

If you're trying to clean grimy grout between your bathroom shower or floor tiles, then OxiClean™ bathroom cleaners are here to help! They get rid of grout stains on vertical and floor tiles for a refreshed bathroom.

Is hydrogen peroxide safe for grout?

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.

What is the best shower grout cleaner?

What We Tested
  • Best Overall: Black Diamond Ultimate Grout Cleaner Spray for Tile with Brush at Amazon $34. ...
  • Best Budget: SALE. ...
  • Best for Showers: Scrubbing Bubbles Grime Fighter Spray at Amazon $4. ...
  • Best for Mold and Mildew: Home Armor Instant Mold and Mildew Stain Remover at Amazon $17. ...
  • Best Scent: ...
  • Best Brush:

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