Clay tile flooring adds timeless charm to homes with its natural look and warm, earthy tones. However, one issue occasionally seen — especially in humid / wet spaces — is efflorescence. If you’ve noticed a white, chalky deposit appearing on the surface of your clay tiles, this article will help you understand what’s happening, why, and how to deal with it effectively.
What is Efflorescence?
Efflorescence is the white powdery deposit that sometimes appears on the surface of clay tiles or grout. It is salt residue brought to the surface by moisture.
While it’s not harmful or permanent, it can affect the appearance of your tiles and may indicate excess moisture within or beneath your floor. See Wikipedia Article
Why Does Efflorescence Happen on Clay Tiles?
Clay is a natural, porous material. It allows a very small amount of water to pass through it.
- Water or Moisture from underneath the tile travels through the tile (e.g., from the screed, or soil).
- This water contains natural salts and will also dissolve salts present in the clay, cement, or mortar.
- When the water reaches the surface and evaporates, it leaves behind these salts as white or grey deposits.
How to Prevent Efflorescence on Clay Tiles During Construction and Before Installation:
Preventing efflorescence starts at the installation stage. Here are best practices:
1. Use a Damp-Proof Layer
Ensure the subfloor has a proper damp-proof course or membrane to block moisture rising from the ground. Consult your Architect / Civil Engineer for suitable suggestions. An under-tile sealer coating on the back side of the tile is best, cost-effective and easy way to prevent efflorescence. Contact us for suggestions or supply of suitable items for our clay tiles. We also sell tiles with under-tile sealer coating applied at the factory too.
2. Let the Floor Base Cure Completely
Before laying the tiles, allow the screed or mortar bed to fully dry and cure. Premature laying traps moisture underneath the tiles.
3. Use Breathable Sealers
Apply a breathable sealer on the top of the tile after installation. It prevents surface moisture from soaking in while still allowing trapped moisture to escape slowly. Consult your civil engineer for suggestions.
4. Choose Low-Salt Materials
Use cement, adhesives, and grouts with low salt content when laying your tiles. Especially, during construction, do not use water that contains too much of dissolved solids.
How to Remove Existing Efflorescence Deposits
If you notice efflorescence on your clay tiles, don’t worry — it can be cleaned effectively with a few simple steps:
1. Dry Brushing
Use a dry stiff-bristled brush (not wire) to sweep off the salt.
2. Mop Lightly
Once brushed off, vacuum or lightly mop the floor to collect the residue. Use water.
3. Vinegar Solution (for persistent cases)
Mix a mild vinegar and water solution (1:5) and apply it with a sponge. The mild acid can dissolve remaining salt deposits.
Test on a small, hidden area first to make sure it doesn’t affect the tile’s finish.
4. Use a Commercial Efflorescence Cleaner
If the vinegar doesn’t help, use a product specifically designed for efflorescence (available at most tile or hardware stores). Contact us for specific recommendations. Always follow the manufacturer's instructions on the cleaner.
5. Apply Sealer After Cleaning
Once fully dry and cleaned, applying a sealer can help prevent recurrence by preventing evaporation of moisture from the tile surface.
How to Prevent Efflorescence from Recurring:
If efflorescence keeps returning on your clay tile floor despite regular cleaning, it's a sign that the underlying moisture problem has not been resolved. To permanently stop efflorescence, it's essential to identify and eliminate the source of water or moisture that is carrying salts up to the tile surface.
Leakage from Plumbing
An often-overlooked cause of persistent efflorescence is leaking or broken plumbing within or near the tiled area. Pipes running under floors or within walls can be wrongly installed or develop small cracks or leaks over time, allowing water to seep into the subfloor unnoticed. Similarly, overflow from overhead water tanks, bathrooms, or nearby taps can cause water to accumulate and slowly migrate through the brick walls and into beneath the tiles. Even intermittent leaks can be enough to activate salt movement and lead to recurring efflorescence. It's important to inspect plumbing lines, overhead tanks, and drainage points to ensure there are no hidden leaks or overflow points contributing to the moisture problem.
Groundwater or Soil Moisture
In ground-floor installations, rising damp from soil is a common culprit — especially in homes with no slab insulation or high water table. Solutions include:
- Improving site drainage and slope away from the building.
- Applying a sealer on the tile may help to an extent.
Seal Cracks and Gaps
Check the open terrace and walls for cracks or potential entry points for rain water. Cracks in walls, floors, or tile joints can allow water to seep in. Seal all visible cracks using suitable waterproof fillers or epoxies, and ensure expansion joints are properly protected with flexible sealants.
Other External Water Sources
Sometimes, the source of water may be flower beds or planters near walls, or improper rainwater drainage. Direct irrigation systems or downspouts away from the tiled areas.
Got Questions or Concerns? We're Here to Help
We understand that dealing with efflorescence can be frustrating — especially when it keeps coming back despite your best efforts. It can take away from the natural beauty of your clay tile floor and leave you feeling uncertain about what to do next. At Sree Murugan Tile Works, we’re here not just as tile makers, but as partners in your flooring journey. Whether you’re facing persistent moisture issues, need help identifying the source, or want guidance on long-term care, we’re always ready to assist and share our experience. Don’t hesitate to reach out — together, we’ll find the right solution to protect and preserve the lasting charm of your clay tiles. Contact us right away!