How to Clean Slate Mildew

How to Clean Slate Mildew
Published: Dec 19, 2009
Updated: Nov 20, 2021
2 minute read

Fortunately, slate mildew can be cleaned using basic household products.

Things You Will Need

  • Bucket or basin
  • 2 spray bottles
  • White vinegar
  • Household bleach
  • Warm water
  • Sponge
  • Clean dry cloth
  • Mild laundry detergent
  1. Fill a bucket or basin with warm water and add about 1/2 cup of mild laundry washing detergent.

  2. Dip a sponge into the laundry detergent solution and use it to scrub the surface of the slate. Get in and around all the crevices in the slate, paying special attention to any grout between the slate tiles.

  3. Rinse the slate with warm water and wipe it with a clean dry cloth. If mildew remains on the slate go to Step 4. If you have removed all the mildew from the slate move ahead to Step 7.

  4. Fill a spray bottle one fifth of the way with household bleach, and add warm water until the bottle is full.

  5. Spray the bleach solution on the slate and the grout making sure to get any areas of heavy mildew. Allow the solution to sit on the slate for 2 minutes.

  6. Scrub the slate with a sponge dipped in warm water. Dry the slate with a clean dry cloth. Repeat this until all the visible mildew is gone from the surface of the slate.

  7. Fill a spray bottle three-quarters of the way with white vinegar. Add water until the bottle is full.

  8. Spray the vinegar and water solution liberally over the slate and any adjacent grout. There is no need to wipe or rinse after spraying the vinegar. The vinegar is a natural deodorant and disinfectant and will inhibit the future growth of mold and mildew.

The Drip Cap

  • Slate is one of the most durable and popular materials used in construction.
  • Fortunately, slate mildew can be cleaned using basic household products.
  • If mildew remains on the slate go to Step 4.
  • Spray the bleach solution on the slate and the grout making sure to get any areas of heavy mildew.
  • Dry the slate with a clean dry cloth.

Photo Credits

Hemera Technologies/AbleStock.com/Getty Images

Hemera Technologies/AbleStock.com/Getty Images

Ashley Friedman

Ashley Friedman graduated from Sarah Lawrence College in 2003 with a Bachelor of Arts in Creative Writing and Social Sciences. She has experience writing copy for the websites of creative professionals, and regularly contributes to several…

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