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Soudal Silirub 1 is a premium quality, low modulus acetoxy-curing silicone sealant, specifically formulated for sanitary, construction and industrial applications. Designed with a thick-bodied, 100% silicone formulation, it offers superior toolability and long-lasting flexibility.
Silirub 1 contains XS1 fungicide, delivering strong resistance against mould growth in high-humidity environments such as bathrooms, kitchens, and wetrooms. It adheres excellently without primer to most common building materials, including glass, ceramic, anodised aluminium, and wood, and provides a durable seal that resists UV radiation, weathering, and extreme temperature fluctuations.
Certified to ISO 11600 F&G 25 LM, Silirub 1 is ideal for sealing traditional sanitary ware, glazing systems, and high-spec industrial joints.
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✔️ Delivers a durable, waterproof seal ideal for bathrooms, kitchens, wetrooms and high-humidity environments.
✔️ Contains powerful XS1 fungicide to prevent black mould growth in sanitary and constantly damp areas.
✔️ Accommodates movement in dynamic joints thanks to its low modulus and permanently elastic formulation.
✔️ Bonds strongly to ceramics, glass, metal, and wood without primer in most typical construction scenarios.
✔️ UV and weather resistant for both interior use and sheltered external sealing applications.
Soudal Silirub 1 is a high-performance, acetoxy-curing silicone sealant formulated for use in demanding sanitary and moisture-prone environments. This one-part sealant cures rapidly upon exposure to atmospheric moisture, forming a permanently elastic rubber seal that resists water ingress and maintains long-term flexibility. Its low modulus formulation allows it to accommodate movement in joints without cracking, making it a reliable choice for dynamic areas subject to thermal expansion or structural vibration.
Specifically designed for sanitary and wetroom applications, Silirub 1 contains XS1 fungicide, which provides superior resistance to black mould growth. This is particularly important in bathrooms, kitchens, wetrooms, and utility spaces where humidity is consistently high and hygiene is critical. Once cured, the sealant becomes fully waterproof, helping to prevent both water penetration and microbial contamination. These features make Silirub 1 an excellent solution for both residential and commercial environments, including hotels, care homes, and public washrooms.
Silirub 1 adheres exceptionally well to a wide range of building materials, including glass, glazed tiles, anodised aluminium, enamel, stainless steel, and some treated woods. In most cases, it performs without the need for a primer, offering convenience and time savings during application. Its UV and weather resistance also make it suitable for sheltered external use, such as sealing around windows, doors, and other perimeter joints where exposure to sunlight and rain may occur.
The thick-bodied consistency of Silirub 1 allows for precise application with excellent tooling properties, ensuring a clean, professional finish. It holds its shape well on vertical surfaces, with minimal sagging, and forms a durable skin within a short time frame. Although its acetic cure system makes it unsuitable for use on sensitive substrates like natural stone or polycarbonate, it is ideal for non-porous materials where strength and moisture resistance are the primary concerns.
Soudal Silirub 1 is not only suited to sanitary installations but also serves well in other building sectors, including mechanical and electrical applications. Its compatibility with ventilation systems, air-conditioning ductwork, and glazed units highlights its versatility. Whether in a residential refurbishment or a commercial fit-out, Silirub 1 offers the long-term durability, hygiene protection, and ease of use that professionals demand from a premium silicone sealant.
Exceptional Mould Resistance: Formulated with XS1 fungicide, Silirub 1 offers long-term protection against mould and mildew growth, even in wet or humid environments such as bathrooms, kitchens and showers.
Primerless Adhesion on Most Surfaces: Bonds effectively to a wide variety of building materials including glass, ceramics, aluminium, stainless steel, and wood, eliminating the need for additional primers or surface treatments in most applications.
Long-Term Elasticity: Maintains its flexibility and performance over time without hardening or cracking, accommodating joint movement and ensuring durability in sanitary and construction joints.
Superior UV and Weather Resistance: Colourfast and resistant to degradation caused by sunlight, moisture and fluctuating temperatures, making it suitable for indoor and sheltered outdoor use.
High Quality Thick-Bodied Formula: Offers excellent application characteristics, allowing for clean, controlled tooling and neat finish in vertical and overhead joints without sagging.
Sealing of Sanitary Ware: Ideal for sealing around baths, sinks, shower trays, toilets, and tiled walls where high moisture levels demand mould resistance and a watertight, flexible joint.
Perimeter Sealing of Frames: Suitable for sealing the internal perimeters of wooden or aluminium window and door frames, offering weather resistance and long-lasting elasticity in fluctuating conditions.
Glazing and Glass-to-Glass Joints: Used for top sealing in glazing applications, including glass partitions, shower screens, and structural glass elements where transparency and flexibility are required.
Air Conditioning and Ventilation Systems: Appropriate for sealing joints and panels within HVAC systems, where resistance to moisture and mechanical vibration is crucial.
General Industrial and Maintenance Sealing: Can be used in a wide variety of general sealing tasks across construction and industrial settings, offering consistent results where movement and moisture are factors.
Always observe standard labour hygiene procedures when using Soudal Silirub 1. Appropriate personal protective equipment such as gloves and eye protection should be worn at all times during handling and application.
Work in a well-ventilated area and ensure adequate ventilation is maintained throughout the curing process. Consult the packaging label and the relevant safety data sheet before use for specific precautions and safe handling practices.
Soudal Silirub 1 offers excellent adhesion to most common construction materials including ceramic tiles, aluminium, stainless steel, enamel, and glass. However, it is not suitable for use on PVC. The product also has no adhesion to polyethylene (PE), polypropylene (PP), polytetrafluoroethylene (PTFE, e.g. Teflon®), or bituminous surfaces.
It is not recommended for use on natural stones such as marble or granite due to the risk of staining; in these cases, Soudal Silirub MA is advised. For polycarbonate surfaces, Silirub PC should be used. A preliminary adhesion and compatibility test is recommended on all substrates prior to full application.
All surfaces must be rigid, clean, dry, and free from dust, grease, oil, old sealants, or any contaminants that could affect adhesion. Porous surfaces should be primed using Soudal Primer 150 to improve bond strength.
Non-porous substrates typically do not require priming but should be cleaned thoroughly with Soudal Cleaner & Degreaser. Proper surface preparation is critical to ensure long-lasting performance of the sealant.
Apply Soudal Silirub 1 using a standard manual or pneumatic caulking gun. The sealant should be applied evenly into the joint, avoiding the inclusion of air pockets.
The bead must make full contact with the bonding surfaces and should be tooled immediately after application using a spatula or similar tool. Tooling should be carried out with the aid of a soapy finishing solution, but it is important that this solution does not come into contact with the joint flanks, as this may hinder adhesion.
Only the tooling instrument should be dipped in the finishing solution. Avoid carrying out this process in direct sunlight to prevent premature drying of the soapy solution.
Coverage will depend on the joint dimensions. As a general guide, a 300ml cartridge will typically yield approximately 12 linear metres in a 5 mm by 5 mm joint. For best results, apply in accordance with standard joint design and depth-to-width ratios appropriate to low modulus silicone sealants.
Please refer to our Guide on How To Measure The Number of Tubes Required For the Job.
Minimum width for joints: 5mm
Maximum width for joints: 30mm
Minimum depth for joints: 5mm
Recommendation sealing jobs: Joint Width = 2 x Joint Depth.
After tooling, allow the sealant to cure fully. Skin formation typically occurs within 20 minutes at standard conditions (23°C/50% relative humidity), with a curing speed of approximately 2 mm per 24 hours.
Once cured, the sealant remains permanently elastic, making it suitable for dynamic joints in sanitary and humid environments. While Soudal Silirub 1 contains a powerful XS1 anti-fungal agent, regular maintenance and cleaning of the sealed area are still required to prevent the growth of mould, especially where water or soap residues may accumulate.
Clean tools and excess product immediately after application using Soudal Swipex Cleaning Wipes or a similar cleaner.
Cured product must be removed mechanically using Soudal Sealant Remover Spray or Soudal Silicone Remover Gel.
Avoid using a soapy solution in full sunlight, and do not allow the solution to contact the bonding surface as it can inhibit adhesion.
Soudal Silirub 1 should not be used in applications where continuous water immersion is expected. It is not suitable for bonding aquariums—Silirub AQ is the appropriate alternative for such use.
This product should not be applied in direct contact with the secondary sealing of insulating glass units or with the PVB interlayer of laminated safety glass. Due to its acidic curing system, certain metals such as copper and lead may corrode upon contact.
White-coloured sealants may exhibit yellowing in acid-rich or UV-deprived environments, but will typically return to their original colour under normal daylight exposure.
Soudal Silirub 1 conforms to LEED standards, contributing to a healthy indoor environment. It meets the requirements of SCAQMD Rule 1168 and USGBC LEED 2009 Credit 4.1 for low-emitting materials, adhesives, and sealants.
If using other reactive sealants in conjunction, ensure that the previously applied sealant is fully cured before applying Soudal Silirub 1.
For maximum performance and durability, all application steps should be carried out under controlled conditions, following best practices in sealant joint design.
A) Soudal Silirub 1 is a premium-grade, low modulus acetoxy-curing silicone sealant specifically developed for use in sanitary, construction, and industrial environments. It is a one-part, moisture-curing sealant with excellent adhesion and long-lasting flexibility. Commonly used to seal around baths, sinks, showers, toilets, tiles, and window or door frames, it performs exceptionally well in humid and high-moisture conditions. Silirub 1 forms a durable, watertight, and permanently elastic seal while resisting mould growth, making it particularly suitable for kitchens, bathrooms, wetrooms, and utility areas. Its robust weather, UV, and temperature resistance also allows for selective outdoor applications in sheltered conditions.
A) Yes, Soudal Silirub 1 is ideal for bathrooms, kitchens, and other high-humidity areas due to its XS1 fungicidal formulation, which offers outstanding protection against mould and mildew. Its waterproof and flexible nature ensures long-term performance around sanitary fittings such as sinks, bathtubs, shower trays, and tiled walls. The product adheres well to smooth, non-porous surfaces like ceramic, enamel, glass, and aluminium, maintaining a hygienic seal even under frequent exposure to water and cleaning agents.
A) Soudal Silirub 1 can be used for external applications provided they are sheltered from continuous weather exposure. Its resistance to UV rays and temperature fluctuations makes it suitable for sealing around windows, doors, and glazed panels. However, for fully exposed or weather-intense environments, it is advisable to select a neutral cure silicone or a dedicated weatherproofing sealant, as Silirub 1’s acetic acid curing system may not be compatible with certain building materials like lead or copper.
A) Yes, Soudal Silirub 1 is enhanced with XS1 fungicide, a powerful mould-inhibiting additive that offers long-term protection against black mould and other fungal growth. This feature is particularly beneficial in wetrooms, kitchens, or utility areas where condensation and moisture accumulation are frequent. While the sealant resists mould development, regular cleaning and ventilation are still necessary to maintain a clean and hygienic seal over time.
A) Soudal Silirub 1 offers excellent adhesion to a wide range of common construction and sanitary substrates. It adheres strongly to glass, glazed ceramics, anodised aluminium, stainless steel, enamel, and some treated wood surfaces. It does not bond to polyethylene, polypropylene, PTFE (Teflon), or bituminous substrates. Additionally, it is not suitable for PVC or natural stone surfaces, where staining or poor adhesion may occur. A compatibility test should always be carried out if the material is unfamiliar or coated.
A) In most cases, no primer is required when applying Soudal Silirub 1 to non-porous, clean surfaces. For porous or less stable materials, such as uncoated wood or concrete, priming with Soudal Primer 150 may be necessary to improve adhesion. Surface preparation is key—ensure all surfaces are dry, clean, and free from dust, grease, or contaminants to achieve the best possible bond.
A) Apply Soudal Silirub 1 using a standard manual or pneumatic caulking gun. Cut the nozzle to the desired bead size and apply the sealant evenly into the joint, ensuring no air pockets form. After application, the bead should be immediately tooled using a suitable spatula or sealant finishing tool dipped in a soapy solution. Avoid letting the soapy water touch the joint flanks, as this may reduce adhesion. Do not apply in direct sunlight or very dry conditions as this may cause premature skin formation before tooling is complete.
A) Soudal Silirub 1 typically forms a skin within 15 to 20 minutes under standard conditions (23°C and 50% relative humidity). Full curing occurs at approximately 2mm per 24 hours. Thicker joints will take proportionally longer to cure. Avoid exposing the joint to water or mechanical stress until the sealant is fully cured to ensure optimal performance.
A) Yes, Soudal Silirub 1 is suitable for use in glass-to-glass and glass-to-frame sealing applications, particularly in interior settings like shower screens, partitions, and glazed doors. It offers clear or colour-matched sealing with excellent adhesion and flexibility. However, it must not be used in direct contact with the secondary edge seals of double-glazed units or with laminated glass containing PVB interlayers.
A) No, Soudal Silirub 1 is not paintable. Like most acetoxy-cure silicones, paint will not adhere properly to its cured surface. If you require a paintable sealant, a different product such as a hybrid polymer sealant from the SMX range should be considered.
A) No, Soudal Silirub 1 is not suitable for use on natural stone, including marble or granite, as it may cause staining due to the acetic acid curing system. For sealing joints on or around natural stone surfaces, a neutral curing silicone like Soudal Silirub MA should be used to prevent discolouration and preserve the appearance of the stone.
A) Soudal Silirub 1 should be applied at temperatures between +5°C and +35°C for optimal results. Once cured, it remains flexible and functional across a wide temperature range from -60°C to +180°C, making it suitable for both hot and cold environments, including use near heating systems and sanitary ware.
A) Standard health and safety precautions should be followed when using Soudal Silirub 1. Work in a well-ventilated area and wear appropriate PPE, including gloves and eye protection. Avoid inhaling vapours during application and curing. Ensure that the sealant is kept away from children and stored in a cool, dry place. Always read the Safety Data Sheet before use.
A) Uncured Soudal Silirub 1 can be removed with Soudal Swipex Cleaning Wipes or a suitable solvent-based cleaner. Once the product has cured, it must be removed mechanically with a blade or scraper. Any finishing residue should be cleaned immediately after tooling to avoid staining or curing in unwanted areas.
A) A standard 300ml cartridge of Soudal Silirub 1 will typically provide around 12 linear metres of sealant when applied in a 5mm by 5mm joint. Coverage will vary depending on the joint dimensions, application method, and tooling technique used. Always calculate your joint dimensions in advance to estimate product requirements accurately.
A) Soudal Silirub 1 is suitable for joint widths ranging from 5mm to 30mm. The minimum recommended joint depth is 5mm, and a general guideline for joint design is that width should be twice the depth (i.e. 10mm wide = 5mm deep). Use backer rods in deeper joints to prevent three-point adhesion and ensure optimal performance.
A) No, Soudal Silirub 1 is not designed for continuous water immersion and should not be used in swimming pools, aquariums, or permanently submerged conditions. For aquarium sealing, Soudal Silirub AQ is specifically formulated to be safe for aquatic life and withstand full immersion.
A) No, Soudal Silirub 1 is free from harmful solvents. It cures through a moisture-activated, acetic acid release system. While the curing process does emit a vinegar-like odour, this dissipates once fully cured and does not pose a long-term health risk in ventilated areas. The product conforms to various low-emission and health safety standards including LEED and SCAQMD Rule 1168.
A) Yes, Soudal Silirub 1 is compatible with mechanical and electrical applications including HVAC systems. It offers strong resistance to thermal cycling, vibration, and moisture ingress—ideal for sealing ductwork, ventilation joints, and other components within air handling systems. It ensures a long-lasting, flexible seal that withstands routine movement and exposure to damp conditions.
A) Store Soudal Silirub 1 in a cool, dry environment away from direct sunlight and frost. The ideal storage temperature is between +5°C and +25°C. When stored under these conditions in its original, unopened packaging, the product has a shelf life of at least 12 months from the date of manufacture. Always check the expiry date before use for guaranteed performance.
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