Why is Dark Grout Turning White and What to Do?

How to Clean Grout

To make a long story short:

Why does a dark grout turn white?

  1. Efflorescence: minerals from the grout or subsoil dissolve in water and rise to the surface as the water evaporates, leaving a white powdery residue.
  2. Exposure to water: Excessive moisture can destroy the pigments in the dark grout.
  3. Harsh cleaning products: Chemicals can destroy pigments or leave a white residue.
  4. Incorrect mixing: Incorrect mixing of the grout can cause colour differences.

What to do?

  1. Clean gently: Use a mild detergent and brush. Avoid using harsh chemicals.
  2. Efflorescence Remover: Purchase a special cleaner that dissolves and removes mineral deposits.
  3. Seal the grout: After cleaning, apply a grout sealant to protect joints from moisture and stains.
  4. Apply a sealant to protect the grout from moisture and stains: If a colour difference persists, use a grout stain to restore the desired colour.
  5. In severe cases, the best option may be to remove and replace the grout.

When using products or methods, always test them on a small area first to avoid further damage.

Have you ever gazed upon your pristine, dark-tiled bathroom and wondered, “Why on Earth is my dark grout turning white?” I’m right there with you. This common, yet baffling phenomenon has left many a homeowner scratching their head. Dive into this article to find out the reasons and, more importantly, the solutions.

Understanding Grout

What is Grout?

Grout is that magical paste that binds your tiles together, ensuring a seamless and firm layout. But like any material, it can undergo certain changes based on various factors.

Grout’s Relationship with Moisture

If grout had a Facebook status with moisture, it would be “It’s complicated.” Moisture can be both a friend and foe to your grout. It’s necessary for the curing process, but too much can cause discoloration.

Types of Grout

  • Sanded Grout
  • Unsanded Grout
  • Epoxy Grout

Each has its own pros and cons, and its own susceptibility to whitening.

Reasons Why Dark Grout Turns White


This is a fancy term for the white powdery substance that sometimes forms on grout. It’s actually salt! As water seeps into the grout, it dissolves soluble salts. When the water evaporates, these salts are left behind, appearing as a white residue.

Using Excessive Water During Cleanup

Ever heard the saying, “too much of a good thing?” Well, using too much water when cleaning up after grouting can lead to a weakened color.

Harsh Cleaning Agents

“Will this bleach make my tiles shine?” Maybe. But it could also be the culprit behind your white grout.

Quality of Grout

Let’s face it, sometimes we skimp on quality. A subpar grout might save pennies but could cost in color consistency.

Prevention: Stop it Before it Starts

Sealing the Grout

Think of sealant as the invisible shield for your grout. It repels unwanted moisture, thereby reducing the risk of efflorescence.

Limit Water Exposure

A gentle touch and minimal water can go a long way in ensuring the longevity of your grout’s color.

Quality Over Cost

Sometimes it’s worth shelling out a bit more for a grout that promises durability and color retention.

How To Treat White Stains on Dark Grout

Natural Cleaners

Did you know that equal parts water and vinegar can be a gentle yet effective cleaner for your grout?

Commercial Cleaners

Several products on the market are designed to tackle grout discoloration. But remember, always do a patch test!

Recoloring Grout

If all else fails, recoloring your grout might be the way to go. It’s like giving your tiles a mini-makeover!

Maintenance: The Key to Long-lasting Grout

Regular Cleaning

A little goes a long way. Regular cleaning can prevent dirt buildup and potential discoloration.

Avoid Harsh Chemicals

Stick to grout-friendly cleaners. Sometimes, simple solutions like baking soda and water can do wonders.

Re-seal Periodically

Every sealant has its life span. Remember to re-seal your grout periodically to maintain that barrier against moisture.

Alternative Solutions

Tile and Grout Renewal Kits

Today, several kits offer an all-in-one solution to renew your tiles and grout, making them look as good as new.

Professional Help

If DIY isn’t your thing or if the problem is too extensive, it might be time to call in the experts.


While dark grout turning white can be a perplexing problem, armed with the right knowledge and tools, it’s entirely manageable. Remember, maintenance is the key, and quality always triumphs. So next time you spot that unsightly white patch, you know just what to do!

Frequently Asked Questions
What is efflorescence?
It's a white powdery residue left behind when water evaporates from the grout, leaving dissolved salts on the surface.
Can I use any cleaner on grout?
No, avoid high pH cleaners. Opt for pH-neutral ones.
How often should I seal my grout?
Ideally, once a year. But it may vary based on traffic and usage.
Is re-coloring grout a permanent solution?
While it can last for several years, it's not permanent. Proper maintenance will prolong its appearance.
Can I replace grout by myself?
Yes, with the right tools and knowledge. However, hiring a professional ensures accuracy and longevity.
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