Not sure on how much sealant you'll need? Use our calculator to find out.
For wet areas, metal roofing, marine joints, and general industrial sealing where movement, moisture, and mould are constant risks, Adheseal N40 Silicone Sealant provides a highly flexible, non-corrosive barrier. This neutral-cure oxime formulation adheres reliably without corroding sensitive metals like galvanised steel or Colourbond, while its added fungicide inhibits fungal and biological growth in hot, humid environments.
N40 Silicone Sealant functions by reacting with atmospheric humidity to cure into a flexible silicone rubber. Because it is a neutral-curing (oxime) system, it does not release corrosive acetic acid during the curing process, making it safe for contact with concrete and zinc-coated or galvanised metals. The cured sealant maintains a waterproof, flexible joint with an elastic recovery of over 90% (ISO 7389) and a Shore A hardness of 20, allowing it to withstand prolonged outdoor exposure, marine environments, and permanent UV contact. For safety-sensitive environments, the cured sealant is safe for use in food preparation areas and is fire tested to AS/NZS 1530.3-1999 with a Smoke Developed Index of 0-1.
This sealant is suitable for internal and external applications across a wide range of materials and trades:
Apply the sealant at temperatures between 5°C and 40°C (the physical property application limit is +5°C to +35°C). All joints must be structurally sound, dry, clean, and free from surface water, dampness, oils, grease, curing compounds, or dust. New concrete must be allowed to cure for at least 28 days to prevent subsequent delamination, poor adhesion, or mould growth behind the joint.
To prevent 3-sided adhesion and ensure the sealant only fixes to two surfaces, use a polyethylene backing rod or release tape. For joints greater than 10mm deep, use a backing rod 25% larger than the joint width. N40 should be applied at a 2:1 width-to-depth ratio. Refer to the joint design parameters below:
Apply the sealant by pushing it ahead of the 45-degree angled nozzle to force the material firmly into contact with both joint faces. Tool the joint with a moistened spatula to achieve a smooth finish before the skin forms (within approximately 15 minutes). Clean off excess wet silicone immediately; cured silicone must be removed by mechanical scraping with a blade, which can be softened beforehand using white spirit solvent.
Yes, N-40 is an anti-fungal silicone specifically designed for hot and humid environments. It resists mould and mildew, making it suitable for shower walls, floors, commercial kitchens, laundries, steam rooms, and spas.
No, it is not suitable for horizontal walkways or other trafficable areas. For natural stone, a stain testing program is recommended before application to ensure compatibility and prevent discolouration.
N-40 uses a neutral (oxime) curing system, which is non-corrosive. This formulation ensures it will not corrode galvanised, zinc-coated steel, or concrete, offering reliable sealing on these sensitive substrates.
Yes, it is formulated to perform reliably across a wide temperature range from -50°C to +150°C. It is also suitable for permanent UV exposure, making it ideal for external applications like roofing.
| Application | Key benefit | Primary trades |
|---|---|---|
| Sealing joints in commercial kitchens and laundries | Inhibits mould and biological growth, meeting green star criteria, ensuring hygiene and durability in wet areas. | Commercial fitters, plumbers, tilers |
| Flexible sealing on roofing (e.g., Colourbond, galvanised steel, Zincalume) | High elasticity (±30% movement) handles structural shifts and thermal expansion. Neutral cure prevents corrosion on metal substrates. | Roofers, plumbers, builders |
| Joints in marine environments and vehicle fabrication | Withstands temperature extremes (-50°C to +150°C), suitable for below-waterline applications (once cured) and provides high permanent flexibility. | Boat builders, vehicle fabricators, transport industry |
| Sealing shower walls and floors, steam and spa rooms | Anti-fungal properties prevent mould and mildew in hot, humid conditions, maintaining a waterproof and flexible joint. | Tilers, plumbers, bathroom renovators |
| General construction and civil applications | Broad adhesion to common building materials, including concrete, glass, and timber, with a low VOC, non-toxic formulation for internal and external use. | General builders, civil contractors, shopfitters |
Surfaces must be structurally sound, stable, dry, and free of dust, loose material, oils/grease, release agents, curing compounds, and other contaminants.
Use a two-wipe process with clean cloths. A suitable cleaner/solvent such as white spirits may be used; change cloths frequently to avoid spreading contamination.
Ensure concrete is cured for at least 28 days and fully dry. Remove dust/friable material so the sealant can key properly.
An adhesion test is recommended. Where primer is necessary, apply with a small brush and allow several minutes for solvent evaporation before sealing.
Use Primer 50A where required after testing.
Use Primer 2001 where required after testing.
Aim for a 2:1 width-to-depth ratio where possible. Internal joints: minimum 5 mm width/depth; external joints: minimum 10 mm. Maximum joint width is 30 mm and depth 15 mm.
For joints greater than 10 mm deep, use a closed-cell polyethylene backing rod about 25% larger than the joint width to control depth.
On flat joints, use a polyethylene tape or release agent so the sealant bonds to two sides only—movement works as designed.
Apply between 5°C and 40°C (installation guide). Cut the nozzle at 45°, keep the tip in contact with both sides of the joint, and apply by pushing sealant ahead of the nozzle to force it firmly into place.
Tool off with a moistened spatula before skin forms (tooling window ~5 minutes) for a smooth joint.
While wet, clean tools and spills with white spirit. Once cured, removal is by mechanical means.
WARNING: This material is hazardous according to health criteria of Safe Work Australia. It may cause an allergic skin reaction and causes serious eye irritation.
Personal protective equipment (PPE) must be suitable for the nature of the work and any hazard identified by risk assessment. Ensure eyewash stations and safety showers are close to the workstation.
Natural ventilation should be adequate under normal use conditions. Avoid inhalation of vapour, mist, or aerosols.
Store in a cool, dry, well-ventilated place out of direct sunlight, between 10°C and 35°C. Keep container tightly closed and upright. Keep away from foodstuffs and incompatible materials. Shelf life is 18-24 months in original packaging. Dispose of contents and container in accordance with local, regional, national, and international regulations.
Proper surface preparation is critical for strong, lasting adhesion. Follow these guidelines to ensure optimal performance of N-40.
Surface prep: All surfaces must be structurally sound, stable, dry, clean, and free of dust, loose material, oils, grease, and other contaminants. For impervious substrates, use the two-wipe process with Acetone or 100% White Spirits, changing cloths frequently. Mask joint edges for a cleaner finish.
Primer: Optional. Adhesion testing is recommended. Apply Adheseal 50A for non-porous surfaces or Everflex Supaprime for porous substrates with a small brush, allowing several minutes for solvent evaporation before sealant application.
Surface prep: Concrete must cure for at least 28 days to prevent mould growth or adhesion failure. Ensure surfaces are free from surface water and continual dampness, and follow general cleaning guidelines above.
Primer: Optional. Adhesion testing is recommended. Use Everflex Supaprime for porous concrete surfaces.
| Property | Value |
|---|---|
| Type of Product | Polysiloxanes |
| Curing System | Oxime |
| Density (Specific Gravity) | 1.03 g/cm3 (Translucent) |
| Shore A Hardness | 20 |
| Elongation at Break (ISO 8339) | 300% |
| Application Temperature | +5°C to +35°C |
| Storage Temperature | 10°C to 35°C |
| Temperature Resistance | -50°C to +150°C |
| Fire Tested | AS/NZS 1530.3-1999 Smoke Developed Index of 0-1 |
| Movement Capability | ±30% |
| Elastic Recovery (ISO 7389) | >90% |
| VOC Content | 43 gm/lt |
| Best Before | 18-24 months in original packaging |
| Cleanup Uncured | White spirit or turpentine |
| Skin Time | Approximately 15-20 minutes |
| Cure Time | 2mm per day at 25°C & 50% humidity |
| Form | Viscous Liquid |
| Odour | Faint odour |
| Solubility | Immiscible in water |
| Specific Gravity (SDS) | ~1.05 Kg/L |
| Pour Point/Range | > 0°C |
Here are some common examples on where Adheseal N40 Slicone Sealant used by our customers.
