Black mould growth is a common problem in many homes across the UK. Typically found in warm and damp areas, bathrooms, kitchens and windows can become havens for the growth of black mould. Not only can this be an eyesore on the sealant around the bath and shower, or windows around your home, but mould can pose a health risk if unaddressed. A danger to those with asthma and respiratory conditions, mould can trigger respiratory health problems, damage fixtures within your home and spread across ceilings, walls and floors.

We understand that as a home or business owner, you strive to maintain a clean, healthy and desirable environment for both yourself and those around you. In this article, we will discuss the causes of black mould growth, how it can be treated and ways in which you can prevent it from returning.

Preventing Black Mould Growth

Prevention is key in ensuring your silicone sealant remains mould free. Here are some important steps to follow to help you reduce the chance of mould growth or the chance of it returning to your home.

Maintain good ventilation

There are a few simple ways to immediately improve the airflow in your home.

Opening a Window

By opening a window straight after a bath or shower, you can quickly and effectively remove steam and humidity from your bathroom.

Using an extractor fan / dehumidifier

Some extractor fans have humidity detectors or can be placed on a timer system so that they switch on automatically. This will remove any excess moisture from the air, ensuring that the humidity is controlled.

Regularly clean your bathroom furnishings

Wipe down all surfaces After each use, wiping down the silicone sealant and its surrounding areas, using a clean, dry cloth can help to remove any lingering moisture and deprives mould of the conditions needed for it to survive and grow.

Try using mould-resistant products

Anti-mould sealant When next selecting a silicone sealant for your home and bathroom, go for a mould-resistant formula. These sealants are specially developed to inhibit mould growth, containing additives and fungicides that provide an extra layer of protection to resist mould growth.

How to Identify Black Mould on Silicone Sealant

There are a few key signs that mould may be present in your home.

Smell

A musty smell can often be the sign that there is mould present within a room. The mould on silicone sealant can initially be very small, so the smell may be the first indicator that there is an issue.

Green / Black Spots

Noticing green or black spots on the silicone sealant and in more severe cases, large black areas, can be a tell-tale sign that there is mould on the sealant.

Surrounding Areas

Due to the quick spreading nature of black mould, the space around the initial area can quickly become affected. For example: windows are a prime source for mould growth, and so the paint on an adjacent wall may appear to crack and wallpaper may start to peel away. In some extreme cases where the growth of mould is due to dampness caused by a leak, you may notice unevenness or bulging in the wall.

Steps to Remove Black Mould Effectively

Natural remedies for Black Mould Removal

Minor mould issues can be removed effectively at home using either natural solutions, a chemical mould remover or bleach. No matter which method you choose to remove the mould, you will need to wear a mask, gloves, and goggles in order to protect your skin, eyes and lungs from any airborne particles. It is important to avoid any direct contact with the mould and its spores, as they can cause allergic reactions and skin irritation.

White Vinegar and Bicarbonate of Soda

1. Vinegar is a natural mould killer that unlike other substances does not contain any harmful chemicals.
2. Mix two parts white vinegar to one part water, ideally in a spray bottle and apply liberally on to the sealant. Leave this to sit for at least half an hour and on larger areas of mould this can be left overnight.
3. Using a cloth or old toothbrush, scrub the affected sealant in circular motions to try and loosen some of the mould. It should start to come away. Make sure to clean and wipe the sealant afterwards.

If the mould will not budge, mix the white vinegar with bicarbonate of soda to make a thick paste, and apply this to the affected areas of sealant. Leave this overnight and repeat the circular motions with the cloth or toothbrush.

Chemical solutions for Black Mould Removal

Bleach

1. Mix a 1:4 part ratio of bleach and water into a spray bottle and shake.
2. Spray the bleach solution on the affected sealant and leave it to sit and evaporate.
3. For really stubborn areas you can soak tissue or cloth in bleach and place on the affected area overnight.
4. Clean the sealant with a cloth and water. Then dry thoroughly.

If using a commercially available mould-remover spray, make sure to fully follow all manufacturer guidelines.

Replacing Silicone Sealant

1. In some cases the mould may be so severe that it may be necessary to replace the sealant entirely. This must be done carefully to avoid damaging the surrounding surfaces.
2. Start by removing any remnants of the old silicone sealant using a sealant remover tool or a sharp blade, such as a Stanley knife.
3. Clean the area thoroughly with a mould and mildew cleaner, removing as much of the mould as possible. Allow the area to dry completely.
4. Cut the tip of the silicone sealant tube at a 45° angle, and load it into a caulking gun.
5. Apply a steady bead of silicone sealant in the gap that needs sealing. Then, using a wet finger or a sealant smoothing tool, smooth the sealant for a precise finish.
6. Paying attention to the product label, let the silicone sealant cure for the time specified. Avoid exposing the freshly sealed area to any moisture during the curing period.

Importance of Regular Sealant Maintenance

Neglecting the upkeep of your silicone sealant is essentially paving the way for its deterioration. Like all other aspects of your home, your sealant requires the same attention and maintenance in order to remain fully functional. Damages in the sealant cause the moisture barrier to weaken, making it more susceptible to leaks and allowing pockets of water to collect underneath the sealant. This is a breeding ground for black mould.

Professional Mould Removal Services

DIY black mould removal methods can be effective for minor issues, however in some instances it is best to seek professional advice.

Extensive and Uncontrollable Mould Growth

If the black mould spans across a large area or has spread to hidden spaces, it would be advisable to contact a professional who will be able to eradicate the mould securely and safely.

Health Concerns

Exposure to airborne mould spores can be dangerous to those with a weakened respiratory system, such as those with asthma. If you or your family members are suffering with persistent respiratory problems or allergic reactions, that seem to worsen at home. This may be a sign of mould-related health issues and it is important to contact a professional, to inspect and determine the source of the mould and the necessary solutions to get rid of it.

Recurring Mould Growth

If you have repeatedly removed the mould growth from the silicone sealant, only to have it return quickly after removal. It is advisable that you contact a professional as there may be an underlying issue that is contributing to the persistent mould growth, and an expert may be able to put long-term solutions in place to prevent another recurrence.