Silicone sealant is found along the length of showers, baths and sinks to stop water from reaching the fixtures. Its rubbery consistency and constant exposure to water and moisture make it the perfect breeding ground for black mould to grow. It’s also one of the hardest areas to clean, especially if there is a build-up of black mould over a few months.  

Here is our quick guide to effectively remove black mould from silicone sealant, how to prevent it and when to call in the professionals.  

Causes of Black Mould on Silicone Sealant 

The bathroom is a natural breeding ground for black mould spores – it provides the perfect damp, warm environment that mould spores love and thrive in. Black mould growth on silicone sealant is not uncommon but if the area is not cleaned regularly, moisture and condensation can build up and create a higher chance for mould to spread. Here are some of the most common causes of black mould growth on silicone sealant:  

• Too many products kept in the shower or bath  
• Inadequate ventilation or lack of natural light  
• Not using exhaust fans while showering  
• Water damage or plumbing problems  
• Naturally high levels of humidity  

How to Remove Black Mould from Silicone Sealant

The way in which silicone sealant dries and its positioning creates problems for effective spot removal. Luckily, removing black mould from silicone sealant requires products that are commonly found around the house. To ensure optimal results, you must have:  

• A basin or bowl  
• Rubber gloves/mask/protective eyewear  
• An old clean toothbrush or hard-bristle brush  
• Vinegar  
• Baking soda 
• Bleach 
• Clean cloth 
• Sponge 

To remove the mould, complete the following:  

1. Mix 1 cup of vinegar and 2-3 tsp of baking soda to create a paste  
2. Use a cloth to transfer a small amount of paste and smooth it along the surface of the sealant until you have made a thick layer of paste over the mould  
3. Leave the paste to sit for 5 – 10 minutes  
4. Use an old toothbrush or bristled brush to scrub the paste away from the sealant  
5. Wet your sponge to clean/rinse the sealant using cool water  
6. For any remaining stains, repeat steps 4 – 6

How to Remove Black Mould from Silicone Sealant with Bleach  

For more stubborn stains you can use bleach:  

1. Mix 1:4 part ratio of bleach and water into a spray bottle and shake well  
2. Spray the solution over the sealant and leave to sit and evaporate  
3. Rise the sealant again with a sponge and water  
4. Dry with a clean towel or cloth 

While there are many home and DIY remedies to remove mould from silicone sealant and the bathroom, never attempt to remove large patches of black mould or a mould infestation. If you find large amounts of mould in your bathroom, it could be a sign of water damage or a plumbing issue. In this case, it is important to seek out a professional mould removal service team in order to eradicate the mould problem permanently.  

If you attempt small amounts of black mould, ensure you are wearing gloves, a face mask and protective eyewear to avoid inhaling black mould spores.   

How to Prevent Black Mould in the Bathroom 

Preventing black mould growth in the bathroom is all about moisture control. This means ensuring the area is adequately ventilated and, if possible, has access to natural light. Black mould growth in silicone sealant cannot always be avoided, however, minimising the humidity levels and moisture build-up can lower the chances significantly.  

If you notice large patches of black mould or mould resurfacing frequently, reach out to a professional mould removal service team. Other ways to prevent mould in your bathroom may include:  

• Regularly ventilate the area with open windows or a dehumidifier 
• Use the exhaust fan while showering and leave it on for 30 minutes after use  
• Clean, wipe and dry shower walls and glass regularly  
• Clean and dry spills or leaks promptly  
• Do not overfill your bath or shower with products  
• Avoid leaving damp clothes, towels or bath mats in the bathroom  
• Clean the bathroom regularly 

When to Call a Mould Removal Professional 

Black mould can be stubborn and often return if there is an ongoing or underlying issue persisting. In these cases, black mould can become a health concern and can easily spread throughout the household. 

If you are afraid of mould becoming a problem in your home and are looking for a long-term solution, be sure to call upon a professional team to help you. The MouldMen team will inspect, treat and provide you with a Mould Management and Prevent Plan to ensure that your home is kept safe and free from black mould. Call us on 1300 60 59 60 to book your free inspection today.