Ask Danny

How to Prevent Mold on Tub and Shower Caulk


I’m constantly replacing the caulk between my shower walls and floor due to mold. How can I prevent mold from forming on the caulking in my shower? -Bill

Hi Bill,

Any time you put caulking in a high moisture environment, such as in a shower or tub, the result is usually mold and mildew. One thing I always recommend is to use 100% silicone caulking in a tub or shower, rather than acrylic caulk. The caulk you use in a tub or shower should also contain a biocide to prevent mold from forming.

While several manufacturers have come out with pretty good mold resistant caulk, I’ve really been impressed with GE Silicone II* K/B Supreme.

Advantages of GE Silicone II* K/B Supreme include:

  • Cures Fast: Can be ready for use in as little as one hour and no more than eight hours (depending on temperature, humidity, and size of the bead).
  • Mold-Free: Contains a biocide that keeps the caulk mold-free for 10 years, if the caulk is cleaned regularly.
  • Waterproof: 100% silicone caulk is and remains waterproof over time.
  • Flexible: 100% silicone caulking doesn’t crack or shrink and remains flexible over time.

Good luck with your project,


Further Information

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4 Comments on “How to Prevent Mold on Tub and Shower Caulk”

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  1. carolyn Says:
    July 10th, 2011 at 2:08 am

    how can i paint over paneling

  2. Official Comment:

    Ben Erickson Says:
    July 19th, 2011 at 9:03 am

    Hi Carolyn,
    You can find the answer to your question about painting paneling in our video on How to Paint Paneling. Good luck with your project!

  3. Liz Kuntne Says:
    August 10th, 2013 at 6:54 am

    On today’s show, 9/10/13,Danny renovated his own bathroom. When the shower was completed, he sprayed the interior with a product that prevented mildew. What is this product and where can I find it? My family just built a house and I would like to treat our showers with this product before the mildew creeps in. Thank you, Liz K.

  4. Official Comment:

    Ben Erickson Says:
    August 10th, 2013 at 8:09 am

    Hi Liz,
    You can find info on the product Danny used to prevent mold and mildew in his shower in the episode article for this week’s show at
    For future reference, you can find a link to to this and last week’s episode articles, as well as a link to a list of all the past episode articles on the TV section of our website by clicking on the “TV” tab in the navigation t the top of every post.

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