Absolute Mould Removal

Does Bleach Kill Mould?

Does Bleach Kill Mould?

Bleach can kill surface mould on non-porous surfaces like glass and tile. However, it does not penetrate porous materials well enough to eliminate root mould. 

Read further as we provide you a comprehensive guide on bleach and its effectiveness against mould and mould spores, in order you can make an informed decision about whether you can try using bleach to kill mould or consider hiring Brisbane Mould Removal team of professionals. 

Does Bleach Kill Mould?

 Porous SurfacesNon-Porous Surfaces
Does Bleach Work?NoYes
CharacteristicsPorous surfaces are great environments for mould growth as they trap moistureNon-porous surfaces do not absorb or trap dirt, so they are easier to clean
ExamplesUnsealed wood, wallpaper, fabric, ceiling tiles, drywall, carpetVinyl, metal, glass, glazed ceramic, porcelain

According to the Queensland Health Gov website, mould grows deep into porous surfaces, such as wood and drywall, so bleach cannot be used effectively on these surfaces.

Moreover, the US Environmental Protection Agency (EPA) advises against regularly using chlorine bleach to remove or clean mould. From carpet cleaning to drywall disinfecting, the EPA suggests utilising mould removal products specifically designed for such surfaces. This way, you can ensure that you thoroughly clean mould and prevent subsequent mould growth.   

Bleach poses health risks as it emits very poisonous gases, especially when combined with ammonia. Furthermore, because bleach contains around 90% water, it can stimulate hazardous mould growth on porous surfaces due to the excess moisture it supplies. Once bleach has been applied, the chlorine soon evaporates, leaving water behind, which, when absorbed by porous surfaces like wood, encourages the growth of mould. Note that mould removal is also called “mold remediation” or “mold cleaning”.

How To Use Bleach To Kill Mould?

How Does Bleach Interact with Mould?

Bleach, scientifically known as sodium hypochlorite, interacts with mould through its active agent, chlorine. The chlorine in the bleach reacts with the mould (and its organic matter), producing a colourless substance, thus giving the illusion that the bleach has killed the mould. It’s important to understand this interaction to effectively approach cleaning the mould.

The Reaction Between Bleach and Mould at the Microscopic Level

At the microscopic level, the chlorine in bleach stays on the surface, removing the colour of the mould, while the water in bleach seeps into the porous material, providing more dampness that encourages mould growth. 

Hence, the bleach does not solve the root cause of mould growth and may exacerbate the situation over time. When mould is treated with bleach, the mould spores can thus remain alive, leading to future mould growth.

How to Use Bleach to Kill Mould

If you still want to use bleach for mould removal, remember that it can be useful on non-porous surfaces. You can create a mixture of bleach and water, then scrub the area with a microfibre cloth. Keep the area well-ventilated, and always wear your personal protective equipment (PPE). Note that this method is not recommended for areas with extensive mould growth. In this case, it is best to call a professional mould removal service.

What Surfaces is Bleach Effective on for Mould Removal?

Bleach is indeed an effective mould removal product. It’s especially useful on hard, non-porous surfaces which do not soak or absorb the bleach solution. This makes it an excellent option for cleaning mould off ceramic tiles, bathtubs, glass, and countertops. Always remember to air dry the cleaned surface and ventilate the area after using bleach.

Bleach on Wood

Wood is a problematic surface when using bleach for mould removal. While bleach can clean the surface mould, it cannot reach the deeper mould growth within the wood. A professional mould removal service would be more effective in this scenario.

Bleach on Metal

Metal is a non-porous surface, so using bleach for mould removal could work quite well. However, prolonged contact with bleach can potentially cause corrosion to the metal.

Oxygen Bleach vs. Chlorine Bleach

Aside from regular bleach, there are other mould removal products available, such as oxygen bleach. Unlike regular bleach, oxygen bleach, which contains sodium percarbonate, does not produce harmful chlorine gas.

What is Sodium Percarbonate?

Sodium percarbonate is an eco-friendly substance that breaks down into hydrogen peroxide when dissolved in water. It is a safe alternative to use as it does not cause the same damage to surfaces as regular bleach and is highly effective for cleaning mould. Hydrogen peroxide acts very much like bleach, however, as it is safer than bleach, it is an excellent choice for carpet cleaning and other sensitive materials.

Bleach Health Risks

Despite the efficiency of bleach for mould removal on non-porous surfaces, it is necessary to understand its possible health risks. Bleach can emit toxic fumes known as chlorine gas, which can cause severe harm if inhaled. 

Chlorine gas can exacerbate symptoms in people with asthma by irritating the respiratory tract and may cause bronchial inflammation and constriction. This can trigger asthma attacks in susceptible individuals. 

Chronic exposure to bleach and chlorine gas may also contribute to the development of asthma in individuals who were previously unaffected. Therefore, it is recommended that those with asthma or other respiratory conditions use alternatives to bleach or ensure good ventilation during and after its use.

Furthermore, bleach can cause skin irritation and eye damage. Always wear protective clothing when using bleach and ensure it doesn’t come in contact with your skin or eyes. 

What Does the CDC Say About Bleach and Mould?

The Centers for Disease Control and Prevention (CDC) recognises bleach’s effectiveness as a mould removal product. They advise that bleach kills bacteria and mould on hard, non-porous surfaces. However, they note the danger that bleach poses through toxic fumes. 

The CDC recommends wearing protective clothing when using bleach and ensuring good ventilation in the area where it is applied. They also echo that bleach should not be used on porous surfaces, suggesting instead to seek a professional mould removal service or use other mould removal products suitable for those surfaces.

Alternatives to Bleach for Mould Removal

Tea tree oil 

Although more expensive, tea tree oil is a potent antifungal agent that can effectively remove mould on various surfaces. Tea tree oil is a natural solution that can effectively kill mould and its spores. 

Combine one teaspoon of tea tree oil with one cup of water, spray it on the mouldy surface, and let it sit for an hour. Afterwards, wipe away with a microfibre cloth. 

Hydrogen peroxide

Hydrogen peroxide is an excellent alternative to bleach as a mould removal product as it can penetrate porous surfaces and kill mould at its roots, preventing mould from returning. Not only does it kill mould, but it can also break down stubborn mould stains on porous surfaces. However, it’s safer to use than bleach, as it doesn’t produce toxic residue or harmful fumes.

Bicarbonate of soda (baking soda) 

Bicarbonate of soda, a household staple, is a beneficial and safe mould removal product. Add a quarter of a tablespoon of bicarb to a spray bottle of water. After spraying the solution on the mouldy area, scrub it with a brush and rinse with water. After spraying once more, allow it to dry. Bicarb not only kills mould, but it also absorbs moisture to help prevent mould regrowth.

White vinegar

Undiluted white vinegar for cleaning mould and fungus off both porous and non-porous surfaces is a great, cost-effective and non-toxic option. Decant undiluted white vinegar into a spray bottle, apply to the mouldy area, scrub the mould away, rinse and wipe off, dry, and air dry the area. It’s that easy! Note: Do not mix vinegar with any other cleaning products as this can produce volatile, dangerous chemicals. 

Preventing Mould Growth

Once you’ve managed to clean and remove mould successfully, it’s essential to take steps to prevent mould from regrowing. Regularly cleaning damp areas, especially bathrooms and kitchens, can reduce the risk of mould growth. Using dehumidifiers and fans can control moisture, discouraging mould growth.

Moreover, cleaning spills and leaks immediately, drying wet items before storage, and limiting indoor plants can all help to prevent mould. By taking these preventative measures, you can maintain a mould-free environment in your home.

Professional Mould Removal Services

Professional mould removal services such as Absolute’s Absolute Mould Removal offer a variety of mould removal products and methods that are far superior to bleach. Professional products contain active ingredients such as hydrogen peroxide, which effectively kills mould and prevents its regrowth. Call our friendly and professional team on 07 2100 4911 or make a booking online.

Bleach FAQs

Does bleach kill bacteria?

In addition to mould, bleach can effectively kill a wide range of bacteria. It destroys the structure of microorganisms on surfaces, making it a good choice for disinfecting countertops, sinks, and tiles. However, it can produce fumes potentially harmful to humans and pets. 

Can the use of bleach produce chlorine gas?

Yes, the use of bleach can potentially produce chlorine gas, especially when mixed with certain substances like ammonia, which can be found in some cleaning products. Exposure to chlorine gas can result in respiratory issues and should be avoided. Always use bleach responsibly, in a well-ventilated area, and never mix it with other household cleaning products.