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Sovereign Masonry Sterilising Wash is a concentrated biocidal treatment formulated to eliminate lichen, mould, algae and bacteria from a variety of external building surfaces.
Containing a Quaternary Ammonium Salt, degreasing agents and other specialist additives, this versatile steriliser is suitable for use on masonry, brickwork, stone, tiles, asbestos cement and more. It can also be used as a surface steriliser prior to the application of coatings such as masonry paint.
Supplied as a 5 Litre concentrate, it must be diluted before use, with one container making up to 25 Litres of ready-to-use solution. Sovereign Masonry Sterilising Wash carries HSE Approval No 6360.
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✔️ Effectively kills algae, moss, mould and bacteria on masonry, stone, render, tiles and concrete.
✔️ Concentrated formula produces up to 25 Litres of powerful biocidal cleaner from each 5 Litre container.
✔️ Prepares surfaces for paints or sealers by removing biological growth and ensuring maximum adhesion.
✔️ Contains no harsh bleaches or acids, making it suitable for delicate surfaces and heritage applications.
✔️ Fast-acting solution with broad-spectrum activity for routine maintenance or pre-treatment before refurbishment.
Sovereign Masonry Sterilising Wash is a high-performance biocidal treatment formulated to cleanse and prepare a wide variety of external surfaces ahead of refurbishment, decoration, or remedial treatment. Developed for professional use, this powerful concentrate combines Quaternary Ammonium Salts with advanced degreasing agents and surfactants to provide thorough surface sterilisation. Its formulation ensures both effective microbial control and deep cleaning, removing visible organic growth such as moss, algae, lichen, and mould, while also neutralising potentially harmful bacteria including E-coli, Salmonella, and Streptococcus.
This sterilising wash plays a critical role in ensuring long-term performance of subsequent surface treatments by delivering a hygienically clean and biologically inactive base. By eliminating surface contaminants and biofilms, it improves the adhesion and effectiveness of follow-on applications such as water-repellent coatings, masonry paints, or renders. Sovereign Masonry Sterilising Wash is particularly effective on substrates including natural stone, brickwork, roof tiles, render, concrete, and asbestos cement, making it an essential product for both general exterior maintenance and more specialised building restoration projects.
The formulation’s active ingredient, Dimethyl didecyl ammonium chloride, ensures rapid and long-lasting biocidal activity without the need for aggressive acids or bleach-based agents. This allows for safe and effective treatment that does not compromise the surface structure or appearance. The product’s ability to penetrate porous substrates enhances its performance, allowing it to reach deeper layers where microbial growth often resides. The result is a thoroughly sanitised surface that is not only visibly cleaner but also protected against regrowth.
Sovereign Masonry Sterilising Wash is especially valuable as part of a larger system in properties undergoing damp remediation or fungal treatment. It is highly recommended as a preparatory stage before the application of more targeted biocides such as Lignum Pro M50 Masonry Biocide, especially in areas where dry rot has been identified. By removing competing surface organisms and neutralising contamination, it helps ensure the success and longevity of these more specialised treatments.
Supplied in a concentrated 5-litre liquid format, each container of Sovereign Masonry Sterilising Wash yields up to 25 litres of ready-to-use solution when diluted correctly. It can be applied with ease using either a brush or low-pressure spray system, ensuring flexible application across vertical and horizontal surfaces. The wash begins to take effect rapidly upon contact, with the active ingredients working to break down organic residues and sanitise the substrate effectively.
Whether part of a scheduled maintenance routine or a pre-treatment in larger renovation works, Sovereign Masonry Sterilising Wash offers a professional and efficient approach to exterior surface preparation. Its powerful cleaning action, ease of application, and compatibility with follow-on protective coatings make it an indispensable tool for contractors, surveyors, and maintenance teams seeking to ensure lasting results in the fight against biological growth and surface degradation.
Sovereign Masonry Sterilising Wash carries the HSE Approval No 6360.
Broad-Spectrum Biocidal Action: Effectively kills a wide range of biological growths including mould, algae, moss and lichen, as well as harmful bacteria such as E-coli and Salmonella, ensuring thorough surface sterilisation.
Versatile Application: Suitable for use on brick, masonry, stone, concrete, asbestos cement, roof tiles and other mineral-based building materials, making it a highly flexible solution for external cleaning.
Pre-Treatment Before Coating: Ideal for preparing surfaces before applying decorative or protective finishes such as masonry paint, improving adhesion and reducing the risk of coating failure due to underlying contamination.
Concentrated Formula: Supplied as a concentrate, allowing for flexible dilution to suit different levels of biological growth and surface contamination, making it cost-effective and adaptable for both light and heavy-duty applications.
HSE Approved: Carries HSE Approval No 6360, providing assurance that it meets recognised safety and efficacy standards for biocidal treatments used on building materials.
No Harsh Bleaches: Free from chlorine or strong acids, reducing risk of substrate damage and making it safer to use on delicate materials such as natural stone or older masonry.
Brickwork and Masonry: Used to treat and sterilise brick and masonry walls suffering from green staining, algae, moss or bacterial build-up, particularly in shaded or damp areas exposed to persistent moisture.
Stone Surfaces: Highly effective on both natural and engineered stone used in facades, garden walls, or stone paving, especially where organic growth creates aesthetic and safety concerns.
Roof Tiles and Asbestos Cement: Can be used to clean tiles and asbestos cement panels (e.g. on garages and outbuildings) prior to repainting or sealing, helping restore appearance and remove biofilm.
Render and Concrete: Useful in refreshing rendered or concrete surfaces ahead of painting or water-repellent treatments, ensuring the removal of bio-contamination that could affect long-term performance.
Pre-Coating Surface Sterilisation: Applied as a preparatory treatment to kill biological organisms before applying exterior masonry paints or breathable coatings, enhancing product adhesion and preventing future contamination underneath coatings.
Flood or Damp Remediation: Suitable for areas where external surfaces have been subject to prolonged damp or water ingress, particularly in flood remediation projects or in shaded corners where biological growth thrives.
Dimethyl Didecyl Ammonium Chloride is a highly effective quaternary ammonium compound (QAC) widely recognised for its broad-spectrum antimicrobial properties. In Sovereign Masonry Sterilising Wash, it acts as a powerful biocide targeting a wide range of microorganisms, including moulds, algae, lichen, and harmful bacteria such as E. coli, Salmonella, and Streptococcus. Its primary mechanism of action involves disrupting the integrity of microbial cell membranes. The positively charged quaternary ammonium ions bind to negatively charged microbial cell surfaces, leading to membrane disintegration, leakage of vital cell contents, and rapid cell death. It is especially effective on porous mineral surfaces like masonry, patios, and concrete, where biological growth is often embedded into surface textures. Its low volatility and long-lasting residue also provide residual biocidal activity, making it particularly suitable for outdoor use in damp, shaded areas prone to microbial colonisation.
This quaternary ammonium-based surfactant is both a cleaning agent and antimicrobial component in Sovereign Masonry Sterilising Wash. It combines the biocidal power of a QAC with surfactant properties that enable deep penetration into porous surfaces. The C12-14 alkyl chain range ensures broad-spectrum surface activity, while the ethoxylate element provides detergent-like characteristics that break down organic soils and biofilms. This not only enhances the product’s ability to kill microorganisms but also physically lifts residues from the surface, improving visual cleanliness and reducing slip hazards caused by biological growth. It is particularly useful for vertical or irregular surfaces where effective wetting and surface contact are crucial. Its inclusion in the formula ensures that active biocides are evenly distributed and retained on the treated substrate, boosting overall efficacy.
C9-11 ethoxylated alcohols are non-ionic surfactants used in this formulation to enhance cleaning and dispersion performance. These compounds act by lowering the surface tension of water, allowing the biocidal solution to spread more effectively across uneven surfaces and penetrate deeply into microscopic pores of masonry, paving, and stone. By emulsifying oils, dirt, and organic deposits, they assist in removing microbial biofilms that protect moulds, algae, and bacteria from treatment. This cleaning action not only improves immediate results but also supports the biocidal agents by ensuring unimpeded contact with the microorganisms. Their low-foaming nature and excellent compatibility with other actives make them ideal for outdoor cleaning applications, especially in high-traffic or frequently damp areas such as patios, driveways, and garden paths.
Together, the active ingredients in Sovereign Masonry Sterilising Wash provide a comprehensive solution for cleaning and sanitising external hard surfaces. Dimethyl Didecyl Ammonium Chloride and Quaternary C12-14 Alkyl Methyl Amine Ethoxylate Methyl Chloride deliver potent and wide-ranging biocidal action against algae, lichen, moulds, and harmful bacteria. These are supported by the deep-cleaning action of C9-11 ethoxylated alcohols, which break down organic matter and biofilms, allowing the biocides to reach and destroy the root structures of biological growths. The synergy between disinfection and cleaning ensures both immediate removal of visible growth and long-term suppression of microbial recolonisation. This makes the product not only an effective masonry, path, and patio cleaner but also a reliable antimicrobial treatment that enhances surface appearance, safety, and hygiene in outdoor environments.
Before use, ensure appropriate personal protective equipment is worn, including gloves, goggles, and protective clothing. Eye and face protection must be used during all stages of application to minimise risk from splashes or contact.
Always read the product label and consult the Safety Data Sheet for full health and safety guidance prior to handling. Avoid contact with skin and eyes, and ensure adequate ventilation during use.
Sovereign Masonry Sterilising Wash is suitable for use on most external building materials including brickwork, stone, render, concrete, roof tiles, and asbestos cement. It is particularly effective on porous and textured masonry substrates where biological growth such as mould, algae or lichen is present.
Painted or previously sealed surfaces are also compatible, although results may vary depending on the porosity and condition of the coating. The product is not intended for use on gypsum plaster or delicate decorative finishes.
All surfaces must be free from loose debris and general soiling prior to application. Remove leaves, dirt and surface dust using a stiff brush or similar tool. For porous masonry, begin by dampening the surface with clean water to reduce suction and aid the penetration of the sterilising solution.
Pre-wetting is not necessary on painted or non-porous surfaces. For severe infestations, leave the solution on the surface for a minimum of 24 hours to allow the active biocides to fully act upon the growth.
Dilute Sovereign Masonry Sterilising Wash at a ratio of 1 part concentrate to 4 parts clean water. A 5-litre container of concentrate will yield 25 litres of ready-to-use solution. Always add the concentrate to the water and stir thoroughly to ensure a uniform mix.
Apply the diluted solution by brush, working it well into affected areas to ensure thorough contact, or use a low-volume spray unit for broader coverage on vertical or irregular surfaces. For heavy contamination, allow the solution to dwell for at least 24 hours before attempting removal. Scrub the surface with a stiff brush or use a power washer to dislodge and rinse off dead biological material.
After removal, a light reapplication of the sterilising wash may help to suppress future growth, although this is not a permanent solution without additional protection.
Coverage rates will vary depending on the method of application and porosity of the substrate.
When applied by brush, expect a coverage of approximately 5 to 9m² per litre.
When applied by spray, the rate is typically between 4 to 6m² per litre. More porous surfaces may require higher volumes for effective treatment.
The solution will begin to act immediately upon contact with the surface. On porous masonry, it should be allowed to remain for at least 24 hours before rinsing or removal. Drying time may be extended in cooler, damp conditions. Reapplication for preventative purposes can be made once the surface is dry.
All tools and equipment should be rinsed thoroughly with clean water immediately after use. Do not allow the diluted solution to dry on application tools or in spray equipment, as residue build-up may impair performance or result in clogging.
While Sovereign Masonry Sterilising Wash provides an effective initial sterilisation, it does not guarantee long-term prevention of biological regrowth.
For prolonged protection, especially on porous masonry, consider follow-up treatments with Sovereign water repellent products to reduce moisture absorption and biological colonisation.
Store the concentrate in its original container in a cool, dry location between 5°C and 25°C, away from direct sunlight and sources of frost. Always use biocides safely and responsibly.
A) Sovereign Masonry Sterilising Wash is a concentrated biocidal treatment designed for the effective removal of mould, algae, lichen, moss and bacteria from external building surfaces. It is commonly used on substrates such as brickwork, natural stone, concrete, render, roof tiles, asbestos cement and other mineral-based materials. Its powerful formulation, containing Quaternary Ammonium Compounds and advanced surfactants, ensures deep sterilisation of both visible biological growth and microscopic contaminants. It plays a vital role in the preparation of surfaces before applying coatings such as masonry paints or water repellents, helping to improve adhesion and prevent the regrowth of microorganisms under new finishes.
A) Sovereign Masonry Sterilising Wash must be diluted at a ratio of 1 part concentrate to 4 parts clean water before application. A 5-litre container will therefore produce up to 25 litres of ready-to-use solution. To ensure proper dilution, always add the concentrate to the water rather than the other way round, stirring thoroughly to achieve a uniform mix. This allows for consistent performance across all treated areas, ensuring effective biocidal action and surface sterilisation without overuse of product.
A) This product is suitable for a broad range of external hard surfaces including brick, stone, render, concrete, roof tiles, paving slabs and asbestos cement panels. Its compatibility with porous and semi-porous mineral substrates makes it highly effective for exterior walls, garden structures, driveways, roofs and boundary features. It can also be used on painted surfaces, though testing on a discreet area is advisable to confirm compatibility, especially where coatings may be old or degraded. The product is not suitable for gypsum plaster or internal decorative finishes.
A) Yes, Sovereign Masonry Sterilising Wash is ideal as a preparatory treatment before painting external surfaces. It removes biological contaminants that could compromise the adhesion and longevity of masonry paints, stains, or protective coatings. By creating a clean and sanitised substrate, it helps to ensure that decorative finishes bond properly and do not suffer from premature failure due to microbial activity beneath the paint layer. Once the surface is cleaned, rinsed and allowed to dry, painting can proceed as per standard guidelines.
A) The diluted solution can be applied using a stiff brush or a low-pressure spray unit. For best results, work the solution thoroughly into the affected areas, ensuring good contact with the surface to allow the biocides to penetrate deeply. On heavily contaminated areas, allow the solution to dwell for at least 24 hours before removal. The surface can then be scrubbed or washed down to remove dead biological matter. Reapplication may be considered if contamination persists or as a preventative measure in high-risk areas.
A) On most surfaces, the solution should be allowed to dwell for a minimum of 24 hours before removal, especially where algae, moss, or lichen growth is substantial. This contact time ensures that the active ingredients fully penetrate and kill biological growth, including spores and embedded biofilms. In cooler, damp weather, drying and reaction times may be extended slightly. Once the treatment period has passed, surfaces can be rinsed or brushed clean as needed.
A) The product contains biocidal agents which can be harmful to plant life if applied directly or if runoff enters garden soil. When using the product near lawns, flowerbeds or planted areas, it is advisable to cover sensitive vegetation with plastic sheeting and avoid overspray or spillage. Any accidental contact should be rinsed thoroughly with clean water. For best practice, apply on calm, dry days and take care not to allow excess runoff into garden borders or drains.
A) Unlike bleach-based alternatives, Sovereign Masonry Sterilising Wash does not rely on harsh chlorinated agents or acids. Instead, it uses quaternary ammonium compounds that offer targeted biocidal action without corroding or discolouring sensitive substrates. This makes it a safer choice for heritage stonework, decorative masonry, or surfaces vulnerable to surface erosion. Furthermore, the formulation has residual antimicrobial effects and penetrates porous materials more effectively, helping to suppress regrowth after treatment.
A) Yes, the product is highly effective for use on roof tiles, slates and asbestos cement sheeting. It helps remove green staining, moss and biological residues that build up on roofs, particularly in shaded or north-facing areas. Apply using a spray or brush, and allow the product to dwell for a minimum of 24 hours before rinsing or scrubbing. Always work safely when accessing rooftops, using proper ladders, safety equipment and, where appropriate, qualified contractors.
A) When diluted at the recommended 1:4 ratio, one 5-litre container will produce 25 litres of ready-to-use solution. Coverage rates vary depending on substrate porosity and the severity of contamination. On average, when applied by brush, expect 5 to 9 square metres of coverage per litre. When sprayed, coverage is generally around 4 to 6 square metres per litre. Heavily porous or highly contaminated surfaces may require additional product or repeat treatment.
A) The product is designed primarily as a powerful initial sterilisation treatment rather than a long-term preventative solution. While it will kill existing biological growth and help delay regrowth, ongoing moisture or shading may lead to eventual recolonisation. To enhance long-term results, follow-up treatments with water-repellent sealers or masonry paints may be recommended, especially in areas prone to damp, moss or algae build-up.
A) No, this product is intended for external use only. It should not be used on internal surfaces, especially in confined or poorly ventilated spaces, due to the strength of the biocides and potential for irritation. For internal mould or fungal growth, alternative products designed specifically for interior use should be selected, following health and safety guidelines appropriate to indoor environments.
A) Appropriate personal protective equipment must be worn when handling and applying the product. This includes chemical-resistant gloves, safety goggles or a face shield, and long-sleeved protective clothing. In spray applications or confined spaces, a mask rated for chemical vapours or mist should also be used. Always read the product label and Safety Data Sheet before use and follow all relevant health and safety guidance.
A) The product contains biocidal substances that may be harmful if ingested or if animals come into contact with treated surfaces before they are dry. Pets and wildlife should be kept away from treated areas during application and until the surfaces are completely dry. Watercourses, ponds and animal feeding areas should be protected from overspray or runoff. Used responsibly and according to instructions, the risk can be effectively managed.
A) Drying time depends on environmental conditions such as temperature, humidity and surface type. Under normal outdoor conditions, the treated surface will begin to dry within a few hours, though a 24-hour dwell time is recommended for effective sterilisation. In damp or shaded areas, the product may take longer to dry fully. Avoid application if rain is forecast within 24 hours to prevent dilution or wash-off of the active ingredients.
A) If rainfall occurs before the solution has had time to dry or dwell for at least 24 hours, its effectiveness may be reduced. This is especially true if rain occurs within a few hours of application. For best results, apply during dry weather with a clear forecast for at least a full day. If rain interrupts treatment, a second application may be necessary to achieve full sterilisation.
A) No, the product is formulated to clean and sterilise without altering the colour or texture of mineral surfaces. It is free from bleaching agents or acids, making it suitable for use on more delicate masonry or heritage stone. However, as with any treatment, it is always advisable to test a small, inconspicuous area first to confirm compatibility and appearance, particularly on coloured or previously treated surfaces.
A) The product contains biocides that are effective but should be used with caution to minimise environmental impact. It does not contain chlorine or aggressive acids, which makes it safer than some traditional disinfectants. However, users must still take care to prevent runoff into watercourses or soil. Follow all disposal guidelines and apply responsibly, ensuring compliance with local environmental regulations.
A) Yes, once the surface has been properly treated, rinsed, and allowed to dry completely, it is suitable for painting with exterior masonry paints or other decorative coatings. The wash helps prepare the substrate by removing microbial contamination that could otherwise impair adhesion or cause failure of the topcoat. Ensure no residues or loose material remain before painting, and always follow the paint manufacturer’s guidelines.
A) Store the concentrate in its original, tightly sealed container in a cool, dry place at temperatures between 5°C and 25°C. The product must be kept out of direct sunlight and protected from frost. Avoid storage in areas where accidental spillage could contaminate drains or soil. If stored correctly, the product will retain its effectiveness for extended periods, providing reliable performance across multiple treatment cycles.
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