How To Remove Mold From Silicone Caulk [Detailed Guide]

Mold thrives in a moist and warm environment. This is why the silicone caulk placed in the bathtub or shower attracts the fungus. Removing the old caulk is a time-consuming project, so you should try cleaning with household staples like bleach or ammonia. These are proven mold removers that have stood the test of time.

Other household cleaners like baking soda and vinegar can even do a better job. Keep in mind that routine cleaning will prevent the mold from leaving behind the dark-colored stains.

A Detailed Guide On How To Remove Mold From Silicone Caulk

The first step is to gather supplies. You need baking soda, bleach, plastic wrap, disposable paintbrush, and a spray bottle. And to ensure you’re well-protected, wear a pair of gloves and a respirator.

The bleach fumes can be detrimental to your health. Also, you may want to wear old clothes just in case the bleach spills on them.

How To Remove Mold From Silicone Caulk With Ammonia

To ensure you don’t inhale the harmful effects of ammonia, you should improve air circulation. Open the windows and doors to get the air moving. In most bathrooms, the airflow is limited so you should wear a respirator to filter out the fumes.

After that, make your solution. This involves mixing equal parts of ammonia in the bottle. Spray on the moldy caulk and wait for a few minutes to work the magic.

Next, scrub the caulk with a small brush and wipe with a cloth to remove all the traces. If the first application didn’t work, repeat the process. It’s worth mentioning that ammonia gives the best results when used on non-porous surfaces.

Sometimes, the silicone caulk may look clean but the mold may still be present. This could be a sign that the mold roots may be too deep in the caulk. The only remedy is to try another solution.

Removing Mold From Silicone Caulk Using Bleach

Start the cleaning process by ventilating the area. While bleach works best on non-porous surfaces, it will do a better job than ammonia. To prepare your solution, mix one cup of chlorinated bleach with one gallon of water.

Stir it until it mixes completely. Soak a sponge into the solution and scrub the problem area. If the quick scrub doesn’t do the job, spray the mixture on the silicone caulk and wait for 15 to 20 minutes. After that, wipe down with the soft sponge.

You can also use a cleaning brush to reach the mold’s roots.

If you notice that the bleach is not reaching the roots, switch o cotton coils. Leave the cotton overnight to ensure it soaks up the bleach. Clean it in the morning and wipe with paper towels.

To prevent mold from growing, you should spray the area again and let it be. Avoid mixing your bleach with ammonia because it can create a toxic reaction. And if you just prayed your caulk with ammonia, don’t use the bleach immediately.

Removing Mold From Silicone Caulk With Non-toxic Mold Killers

The most common household cleaning agents include vinegar, baking soda, borax, and hydrogen peroxide. They are inexpensive and are available in your local store.

It’s scientifically proven that vinegar can kill more than 82% mold species. To kill the fungus, you should spray on the silicone caulk and let it work for a couple of minutes. Use a sponge to wipe away the mold. For best results, you should apply white distilled vinegar. This remedy is effective in removing the stubborn black mold.

Baking soda will kill the mold and absorb the moisture on silicone caulk. Put some a half teaspoon of vinegar in the spray bottle and mix with some water. Shake well until it dissolves completely. Spray on the caulk, scrub with a brush, and rinse with water. This remedy will prevent the mold from returning in the future.

Hydrogen peroxide exhibits antiviral, anti-fungal, and antibacterial properties. Before you apply it on the silicone caulk, you should ensure it has a concentration of 3%. Fill a bottle with the solution and spray the caulk. Allow the cleaner to settle in for 10 minutes and then scrub with a brush. Once you remove the mold, wipe with a clean cloth.

Borax is another natural choice for removing mold. Apart from eliminating the fungus, it disinfects the surface. Mix borax and water in a 1:1 ratio and clean the affected area. Spray the solution on the caulk and allow it to sit for 10-15 minutes.

Scrub the area with a soft brush before rinsing it off. Once you’re done, don’t clean the cleaning solution because it acts as a natural deterrent to mold. Unlike other cleaning solutions, you can mix borax with vinegar.

Just mix equal amounts and scrub the silicone caulk. If this doesn’t work, check the expiry date of your bleach.

Once you clean the silicone caulk, you should disinfect the rest of the surfaces to avoid re-growth of mold. The most effective way of removing the invisible spores is to spray the shower stall with bleach.

Be sure to perform this simple task for a couple of days to avoid the re-occurrence of mold.

How Mold Forms On Silicone Caulk

Mold grows in areas where there’s too much moisture. When the humidity level is above 60%, mold spores will attack the caulk and begin to multiply. Likewise, if a rigid caulks lose adhesion the water gets behind it which leads to mold growth.

How To Prevent Mold From Forming Behind The Silicone Caulk

The easiest way to prevent mold is to reduce moisture in your bathroom. Once you take a bath, you should leave the shower enclosure open. This will ensure the area dry out fast. Apart from that, you should turn on the vent fan to allow in clean air.

Run it for 30 minutes after taking a shower. Another preventive measure is to dry the walls and other areas that have caulk. This prevents mold from getting a foothold. When cleaning your bathroom, use a solution that contains bleach.

Be sure to follow the instructions to attain the best possible results. Avoid using alcohol and other strong chemicals that may weaken the silicone. Lastly, you can use a dehumidifier to set the humidity levels between 30-50%.


Mold is an unwelcome visitor in your bathroom. It’s not only ugly but also harmful to your health. If you spot some mold growth on the silicone caulk, you should take the necessary steps to remove it.

You can either use the chemical or non-toxic household cleaners. Remember, if you don’t address the problem immediately the mold spores will spread at a staggering pace.