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Wykamol MCS3 Fungicidal Paint Additive is a highly effective solution designed to prevent the recurrence of black mould and fungal growth in high-moisture environments.
Supplied in 100ml bottles, it is added directly to decorative finishes such as emulsion, gloss, primer, undercoat, varnish, wallpaper paste, textured paint, grout or tile adhesive.
When used correctly—following a thorough surface clean with MCS1 Mould Clear Solution—MCS3 provides long-term protection against mould spores for up to five years. Suitable for use in areas prone to condensation and poor ventilation, including kitchens, bathrooms, and utility spaces.
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✔️ Mixes easily into most paints and coatings without affecting colour, coverage, or drying time.
✔️ Provides long-lasting mould protection by forming a fungicidal barrier within the cured paint film.
✔️ Compatible with emulsions, glosses, primers, adhesives, wallpaper pastes, and tile grouts.
✔️ Ideal for high-condensation areas like kitchens, bathrooms, wet rooms, and laundry spaces.
✔️ One 100ml bottle treats up to 5 litres of paint, offering economical and convenient coverage.
Wykamol MCS3 Fungicidal Paint Additive is a professional-grade biocidal solution developed to address the persistent issue of mould growth in areas prone to condensation and high humidity. Formulated for seamless integration into a wide variety of decorative finishes, this additive enhances the anti-fungal properties of paints, adhesives, grouts, and pastes without altering their colour, texture, or drying time. Its effectiveness in preventing the regeneration of fungal spores makes it a vital component in long-term mould control strategies across domestic, commercial, and public sector properties.
As a key element of the Wykamol Mould Control System, MCS3 Fungicidal Paint Additive is designed to be used in conjunction with MCS1 Mould Clear Solution. Once surfaces have been cleaned and sterilised using MCS1, MCS3 is added directly to the final decorative product to deliver long-term fungicidal protection. This ensures that mould is not only removed but also prevented from returning, particularly in moisture-prone areas such as bathrooms, kitchens, laundry rooms, and poorly ventilated spaces.
MCS3 offers exceptional versatility, allowing it to be used with both water-based and oil-based paints, including matt and silk emulsions, gloss finishes, undercoats, and primers. Its compatibility extends to textured coatings, wallpaper adhesives, tile grouts, and sealants, making it suitable for comprehensive treatment across full interior surfaces. By incorporating the additive into common finishes, users can transform standard materials into active barriers against fungal contamination, ensuring that decorative surfaces remain clean, hygienic, and visually appealing.
Unlike surface-only mould removers or basic anti-mould treatments, Wykamol MCS3 works from within the dried coating layer. Once cured, the biocide remains active in the paint film, delivering ongoing protection against airborne fungal spores and moisture-induced growth. This embedded action is particularly effective in damp or high-condensation areas where traditional coatings may fail. The result is a more durable and health-conscious interior finish that supports improved indoor air quality and surface hygiene.
Each 100ml bottle of Wykamol MCS3 is sufficient to treat up to 5 litres of decorative product, offering outstanding coverage and value for both trade professionals and home users. Its straightforward mixing process makes it easy to incorporate into existing workflows without additional tools or technical adjustments. By extending the lifespan of painted surfaces and significantly reducing the risk of mould recurrence, MCS3 delivers not only visual and functional improvements but also long-term cost savings on maintenance and redecoration.
Wykamol MCS3 Fungicidal Paint Additive provides a reliable and efficient solution for maintaining mould-free interiors in any environment where moisture and poor ventilation present a risk. Its integration into decorative coatings ensures lasting resistance without compromising on finish quality or design. Whether used in new builds, refurbishments, or ongoing property maintenance, MCS3 is an essential tool for achieving cleaner, safer, and more durable living and working spaces.
MCS3 Paint Additive carries the HSE Approval No 7656.
Long-Term Mould Protection: Provides up to five years of protection from mould regrowth when used in conjunction with MCS1 Mould Clear Solution and applied correctly. This reduces the need for frequent redecorating and ongoing remedial work.
Wide Material Compatibility: Formulated for use in a broad range of decorative finishes including emulsions, gloss paints, primers, undercoats, wallpaper pastes, varnishes, textured paints, grouts and tile adhesives, making it a flexible solution for whole-room coverage.
Ideal for Condensation-Prone Areas: Effective in environments with high humidity such as kitchens, bathrooms, utility rooms and laundry spaces where poor ventilation and airborne moisture frequently lead to persistent mould issues.
Does Not Affect Paint Properties: Will not alter the drying time, consistency, colour or application method of most decorative coatings, ensuring that performance and appearance are maintained while offering enhanced protection.
Convenient to Use: Supplied in easy-to-handle 100ml bottles, each treating up to 5 litres of paint or adhesive, MCS3 is simple to dose and mix, making it accessible for both professional and domestic users.
HSE Approved Biocidal Formulation: Contains 3-Iodo-2-Propynyl-n-Butyl Carbamate (IPBC) at 14.85% w/w and is approved under HSE No. 7656, ensuring safety and efficacy when used in accordance with guidelines.
Bathrooms and Shower Rooms: Bathrooms are one of the most common areas for condensation and mould growth due to steam and poor airflow. Adding MCS3 to paints and finishes in these spaces significantly reduces mould recurrence on ceilings, walls, and window reveals.
Kitchens and Utility Rooms: These rooms often experience elevated moisture levels from cooking, washing and drying clothes. MCS3 helps protect painted or papered finishes from unsightly and damaging black mould over time.
Living Rooms and Bedrooms with Poor Ventilation: In older properties or homes with limited airflow, mould can develop in corners, behind furniture, and on cold exterior walls. MCS3 is ideal for treating these areas to prevent surface deterioration and airborne spore build-up.
Rental Properties and Housing Associations: Landlords and maintenance teams benefit from long-lasting mould control that reduces the frequency of call-backs, repainting and tenant complaints. MCS3 is cost-effective and reliable for both new lets and refurbishments.
Healthcare and Childcare Environments: Ideal for use in hospitals, care homes, nurseries and schools, where cleanliness and hygiene are critical. Helps maintain sanitary wall finishes without introducing harmful odours or toxins.
Wallpapered and Tiled Surfaces: Can be mixed with wallpaper paste or tile adhesives to provide built-in mould resistance at the point of adhesion, ensuring that even behind-the-scenes surfaces benefit from preventative treatment.
3-Iodo-2-Propynyl-n-Butyl Carbamate (commonly abbreviated as IPBC) is a broad-spectrum fungicide renowned for its effectiveness in preventing fungal growth on decorative coatings, and it is the key active ingredient in Wykamol MCS3 Fungicidal Paint Additive at a highly potent concentration of 14.97% w/w. IPBC works by disrupting essential enzyme systems within fungal cells, inhibiting respiration and cell division, which halts growth and ultimately leads to the death of mould and mildew organisms. Its efficacy is particularly strong against a wide range of surface fungi, including those commonly found in damp, humid, or poorly ventilated areas such as bathrooms, kitchens, and basements.
When mixed with water-based or solvent-based products—such as emulsion paint, primer, undercoat, varnish, or even wallpaper paste—IPBC integrates seamlessly into the applied film, offering long-lasting fungicidal protection without affecting the appearance or performance of the coating. Once applied to a surface, the active ingredient forms an invisible biocidal barrier that prevents spores from settling and colonising, significantly reducing the risk of visible mould reappearing over time. IPBC’s low volatility and excellent compatibility with most decorative and protective finishes make it especially valuable in both residential and commercial environments.
A 100ml bottle of MCS3 containing this active is sufficient to treat 5 litres of paint or similar medium, providing a simple yet highly effective method of incorporating mould protection into decorative works without altering finish or texture.
Before using Wykamol MCS3 Fungicidal Paint Additive, it is essential to take appropriate health and safety precautions. Personal Protective Equipment (PPE) must be worn throughout the mixing and application process.
This includes protective gloves, goggles, a face mask and suitable overalls to avoid contact with the skin, eyes, or respiratory system. As with all biocidal products, MCS3 must be handled with care. Always read the label and product safety information before use and refer to the relevant Safety Data Sheet for comprehensive guidance.
Do not eat, drink or smoke while handling the product, and ensure that it is kept out of reach of children and pets.
Wykamol MCS3 Fungicidal Paint Additive is suitable for use in a wide variety of environments and on a broad range of internal substrates. It is compatible with most water-based and oil-based decorative finishes including emulsion, gloss, primers, undercoats, textured coatings, wallpaper paste, grouts and tile adhesives.
It is designed for use in areas where condensation and high humidity are present, such as kitchens, bathrooms, laundry rooms and poorly ventilated bedrooms or living areas. For best results, it should be used on sound, previously cleaned and mould-treated surfaces.
Surfaces to be treated must be thoroughly cleaned and sterilised using Wykamol MCS1 Mould Clear Solution prior to the application of any paint or decorative coating containing MCS3 Additive. Refer to the Wykamol MCS1 data sheet for full guidance on application.
Failure to adequately remove existing mould spores and contamination before painting may reduce the effectiveness of the treatment. Once cleaned, surfaces should be dry, stable, and free from loose particles, dust, grease or flaking paint.
Wykamol MCS3 Fungicidal Paint Additive is supplied in 100ml bottles and is designed to be mixed into 5 litres of paint or other decorative finish. The additive should be poured directly into the paint tin or mixing vessel and blended thoroughly using a clean mixing stick or mechanical stirrer.
Mixing should continue for at least one minute, or until the additive is fully dispersed throughout the paint. It is important to ensure even distribution of the biocidal agent to achieve consistent protection across all coated surfaces. Only mix what is needed for immediate use, and do not store any leftover mixed product for future applications.
Apply the treated paint or finish in accordance with the manufacturer’s instructions. This may be by brush, roller or spray, depending on the type of product used. During application and drying, ensure that the room is well ventilated by opening windows and internal doors to promote airflow and assist with curing.
Maintain a consistent coating thickness to ensure optimum mould resistance. Areas prone to condensation or historic mould growth should be given special attention and may benefit from two full coats.
Each 100ml bottle of MCS3 Paint Additive is intended to treat 5 litres of paint, which will then cover an area typical of that paint type—usually around 25 to 35 square metres per coat, depending on the porosity of the surface and the method of application. The additive does not affect the coverage rate of the paint, but full coverage of mould-prone areas is essential for long-lasting results.
Wykamol MCS3 Paint Additive is part of the MCS Mould Control System and is most effective when used following full surface cleaning with MCS1 Mould Clear Solution. When used as directed, MCS3 offers up to five years’ protection against the recurrence of mould growth in areas affected by damp and condensation.
The additive should be stored in its original, sealed container, in a dry, frost-free environment, at temperatures between 5°C and 40°C. Do not expose to direct sunlight or extremes of heat. For long-term mould prevention, good ventilation and moisture control should always be maintained within the treated property.
A) Wykamol MCS3 Fungicidal Paint Additive is a professional-grade biocidal solution designed to prevent the recurrence of black mould and fungal growth in areas prone to high humidity and condensation. Supplied in 100ml bottles, it is added directly to decorative finishes such as emulsion, gloss, primers, wallpaper paste, grout, or tile adhesive. It works by incorporating a fungicidal agent into the paint film, forming a long-lasting barrier that resists mould development on interior surfaces. It is ideal for kitchens, bathrooms, utility rooms, and other poorly ventilated areas where condensation tends to cause surface mould.
A) Wykamol MCS3 Fungicidal Paint Additive works by introducing a powerful fungicide—3-Iodo-2-Propynyl-n-Butyl Carbamate (IPBC)—into decorative coatings. Once applied and dried, this active ingredient becomes embedded within the paint film, providing long-lasting resistance to mould spores. It inhibits the growth of fungi by disrupting their cellular processes, ultimately preventing colonisation on the treated surface. The additive does not act as a surface wash but instead ensures that the protective agent remains effective within the coating itself for several years, making it more resilient to moisture and condensation compared to surface-only treatments.
A) Wykamol MCS3 Fungicidal Paint Additive is intended for use on interior surfaces that are vulnerable to condensation and high humidity. These include walls and ceilings in bathrooms, kitchens, laundry rooms, and poorly ventilated bedrooms or living spaces. It can be used on painted surfaces, wallpapered areas, timber features, tiled zones, and even within tile adhesive or wallpaper paste. It is particularly beneficial in older properties or rooms with cold external walls, where moisture often leads to recurring black mould.
A) Wykamol MCS3 is designed for wide compatibility with most water-based and solvent-based decorative products. This includes emulsion paints, gloss finishes, primers, undercoats, textured coatings, wallpaper pastes, grouts, and tile adhesives. It mixes easily without affecting the consistency, colour, or drying time of the host product, making it suitable for both smooth and textured decorative applications. However, it is always advisable to conduct a small test to confirm full compatibility before applying to a large area.
A) Yes, Wykamol MCS3 is safe for use in homes, offices, schools, hospitals, and other occupied environments when used as directed. It carries HSE Approval No. 7656, confirming that it meets stringent UK safety standards for biocidal products. During application and drying, appropriate ventilation should be maintained, and Personal Protective Equipment (PPE) must be used. Once dried, the treated surfaces are completely safe and non-toxic, offering reliable long-term mould protection without releasing any harmful vapours.
A) When used correctly, and applied following thorough cleaning with Wykamol MCS1 Mould Clear Solution, Wykamol MCS3 can provide mould protection for up to five years. This longevity depends on maintaining reasonable humidity and ventilation levels within the treated area. The biocidal component becomes locked into the paint film, continuing to work long after the initial application by deterring mould spores from taking hold on the surface.
A) Before applying any paint or adhesive mixed with Wykamol MCS3, all affected surfaces must be thoroughly cleaned and sterilised using Wykamol MCS1 Mould Clear Solution. This includes painted walls and ceilings, wallpapered areas, timber mouldings, and tiled regions. The MCS1 treatment eliminates existing mould spores, creating a safe and sterile base that ensures the effectiveness of MCS3 is not compromised by underlying contamination.
A) No, Wykamol MCS3 is formulated to be fully compatible with most decorative coatings and does not alter the colour, finish, consistency, or drying time of the paint or adhesive it is mixed with. This ensures that performance and aesthetic qualities are preserved while adding long-term protection against mould growth. It is still important to stir the mixture thoroughly for even distribution.
A) One 100ml bottle of Wykamol MCS3 Fungicidal Paint Additive is designed to treat 5 litres of paint, wallpaper paste, tile adhesive or grout. This ratio ensures that the biocidal agent is distributed at the correct concentration to provide effective, long-term protection without affecting the decorative product’s usability. It is important to mix the additive thoroughly into the full 5 litres for best results.
A) To achieve an even distribution of the active ingredient, the full contents of a 100ml bottle of Wykamol MCS3 should be added to 5 litres of the chosen paint or adhesive. Stir continuously for at least one minute using a clean stirrer or mechanical mixer, ensuring that the biocide disperses evenly. Avoid using contaminated or dirty tools during the mixing process, as this may affect the additive’s efficacy.
A) It is recommended to only mix what you need for immediate use. While the additive does not cause the paint to spoil, storage after mixing may reduce the stability of the biocidal component and compromise its long-term performance. Any unused mixed product should be tightly sealed and used as soon as possible, avoiding prolonged storage periods.
A) Yes, paint or other finishes containing Wykamol MCS3 can be applied using a brush, roller or spray equipment, in line with the base product’s normal application instructions. Ensure even coverage, particularly in corners, around windows, and on previously affected surfaces. Always maintain good ventilation during application and drying to assist with curing and ensure a healthy indoor environment.
A) Drying time will be the same as the base paint or adhesive product used, as Wykamol MCS3 does not affect the drying characteristics. In most cases, emulsion or water-based paints will dry within 1 to 2 hours under normal indoor conditions. Solvent-based products may take longer. Always check the manufacturer’s guidance for the specific product you are using.
A) Yes, Wykamol MCS3 can be added to wallpaper paste or tile adhesive to provide mould resistance beneath decorative finishes. This is particularly useful in bathrooms and kitchens where wallpaper or tiles are used on walls vulnerable to condensation. It helps to prevent mould from forming behind these finishes, which can be difficult to detect and treat once installed.
A) Wykamol MCS3 is ideal for use in environments such as hospitals, care homes, schools, and nurseries where hygiene is paramount. When used correctly, it provides a safe, non-toxic means of maintaining mould-free surfaces without introducing harmful odours or aggressive chemicals. Always ensure that any cleaning or treatment processes are carried out in accordance with relevant health and safety policies.
A) Wykamol MCS3 should be stored in a cool, dry place away from direct sunlight and extremes of temperature. When stored in its original, sealed container at the recommended conditions (between 5°C and 40°C), the additive has a shelf life of 12 months. Once opened, it is best to use the entire contents within a short period to maintain full potency.
A) Wykamol MCS3 is designed specifically for interior use and should not be used in external paints or coatings. The active ingredients are formulated for indoor conditions and may not provide effective protection or stability when exposed to outdoor elements such as UV light, wind, and rain. For external mould prevention, consult alternative treatments developed for outdoor use.
A) When handling Wykamol MCS3, wear gloves, protective eyewear, and a mask to avoid contact with skin, eyes, or inhalation of any mist. Do not eat, drink, or smoke during application. Always ensure adequate ventilation, and wash thoroughly after handling. Keep the product out of reach of children and pets. For full safety information, refer to the product label and Safety Data Sheet.
A) Failing to clean the surface with Wykamol MCS1 before applying paint or adhesive containing MCS3 can reduce the effectiveness of the treatment. MCS1 is designed to sterilise and remove active mould spores, preparing the substrate for fungicidal protection. If spores are left untreated beneath the coating, they may continue to grow and eventually compromise the decorative finish.
A) Wykamol MCS3 is part of the MCS (Mould Control System) because effective mould prevention involves more than just one step. While MCS3 provides long-term resistance within the finish, it must be preceded by a thorough clean and sterilisation using MCS1 to ensure the surface is free of spores and contamination. Together, they deliver a comprehensive and professional-grade solution that not only treats existing mould but also prevents its recurrence for up to five years.
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