repair moldy caulk Moldy sealant is a common issue that can quickly make a bathroom look aged and unsightly. The sealant or caulking around your plumbing fixtures is easy pickings for household mold and mildew with an ideal combination of warmth, moisture, and organic materials such as soap, skin cells, or food particles. The issue can be compounded by aging or low-quality sealant, inadequate ventilation, or a lack of regular cleaning. To help prevent mold from taking hold bathroom surfaces should be regularly cleaned. Keep the bathroom as dry as possible and do not let water rest on countertops, floors, tubs/showers, and other surfaces. Pay special attention to corners and areas that you may not see regularly such as the top of the shower enclosure.

Proper ventilation in bathrooms is essential in preventing mold. Keep your bathroom exhaust vents clean and check their effectiveness using the “tissue test”. Your fan should create enough suction to hold a square of toilet tissue in place while operating. For more information on these methods you can read this article: Cleaning Your Bathroom Exhaust Fan.

If you don’t have an exhaust fan in your bathroom, we recommend having one installed to prevent mold and other issues associated with excess moisture inside the home.

Moldy Caulk If you do find mold growing on your bathroom sealant, it’s important to act promptly to prevent mold from spreading. If the material appears to be in good shape and is still creating an effective seal you can attempt to clean it with a solution of baking soda and vinegar. Mix the two together to form a paste and cover the moldy sealant with a thick layer. Let the paste sit for 5 – 10 minutes before brushing with a toothbrush. Rinse with a sponge and repeat as needed. If the mold or stains persist you can attempt cleaning with a 1:4 part solution of bleach and water. Spray the bleach on the sealant, let it dry, wipe with a damp sponge, and dry the area thoroughly.

If the mold returns or can’t be removed using the methods described, it’s likely time to replace your sealant. Modern high quality bathroom sealant is often formulated to be mold and mildew resistant and is sometimes guaranteed against mold growth with proper cleaning. Existing sealant can be removed using a caulk remover or knife. Be sure all sealant is completely removed and the area has been thoroughly cleaned and dried. Apply new sealant with a caulking gun held at a 45-degree angle. Keep even pressure on the caulking gun’s trigger to apply a smooth even bead around the entire fixture. Use a caulk finishing tool or dip your finger in water to smooth the bead and create a neat finish. Clean the area thoroughly to ensure any spilled sealant doesn’t dry. After the initial application has dried, double-check your work for any gaps or cracks that should be filled. You should also consider having an HVAC technician evaluate ventilation of the space.

Watch the video below for more information on replacing bathroom sealant, and be sure to use a high-quality product that is specifically designed for use in bathrooms.