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When dynamic movement in expansion joints challenges your seal, or when industrial-grade flexibility is non-negotiable, N-70 delivers. This neutral curing silicone sealant creates a permanently elastic, waterproof seal that accommodates significant joint shifts. Achieve a durable finish that resists UV, extreme temperatures, and general weathering.
Adheseal N-70 was formulated as an industrial-grade neutral curing silicone sealant to solve the problem of premature joint failure in high-movement applications. It provides exceptional flexibility and durability where typical sealants break down. Designed to accommodate significant joint movement, it delivers a long-lasting, permanently elastic, and waterproof seal for demanding construction and industrial applications. Unlike some general-purpose silicones, N-70 is engineered for resilience and performance in challenging environments, curing to a matt grey finish.
N-70 is supplied in 600ml foil sausages for efficient application with a standard caulking gun. Apply it between 5°C and 40°C. Its easy-to-tool formulation allows for rapid drying and smooth finishing within approximately 15 minutes of skinning time. For optimum adhesion and long-term performance, ensure all surfaces are clean, dry, and free of contaminants. Impervious surfaces benefit from a two-wipe cleaning process using Acetone or white spirits. Masking joint edges provides a cleaner finish. For porous substrates, an adhesion test is recommended, with Adheseal Everflex Supaprime used when necessary. For non-porous surfaces, use Adheseal 50A Surface Prep.
Maintain a 2:1 width-to-depth ratio for the joint, with a minimum 5mm width and depth for internal applications, and 10mm for external. For joints deeper than 10mm, use an Adheseal backer rod to control sealant depth and prevent three-sided adhesion, ensuring the sealant only bonds to two opposing surfaces. Clean tools and spills with white spirit while the product is still wet. Once cured, mechanical removal is necessary.
In many construction and industrial settings, Adheseal N-70 serves as a critical final sealant. When you're working on Joint Sealants - Glazing, this product is often the first step in creating the primary weather seal, before any cover trims or facade elements are installed. This positioning ensures maximum adhesion to the primary substrates, delivering a watertight and flexible barrier that protects the building envelope. Ensure all surfaces are properly prepared, and apply any necessary primers like Adheseal 50A Surface Prep for non-porous materials or Everflex Supaprime for porous substrates before applying N-70.
Yes, Adheseal N-70 is a neutral (oxime) cure silicone. This chemistry prevents corrosion on galvanised steel, Zincalume, Colorbond, and other common metals, unlike acidic cure silicones.
Adheseal N-70 accommodates joint movement up to ±50% of the original width. This high elasticity ensures the seal remains intact in dynamic expansion and control joints.
No, Adheseal N-70 is not paintable. Silicone sealants generally repel paint, and attempting to paint over them will result in poor adhesion and flaking.
No, N-70 requires atmospheric humidity to cure properly. It will not cure in totally confined spaces where humidity cannot reach the sealant.
| Application | Key benefit | Primary trades |
|---|---|---|
| Expansion and control joints in masonry and concrete | Accommodates ±50% joint movement to prevent cracking and maintain seal integrity in driveways and walkways. | Masons, landscapers, civil contractors |
| Perimeter sealing around windows, doors, and curtain walls | Provides a durable, weather-tight seal that resists UV degradation and maintains flexibility for long-term performance. | Glaziers, builders, window installers |
| General glazing and glass partitions | Achieves a superior bond to glazed surfaces and glass without corroding adjacent materials, ensuring a long-lasting, flexible seal. | Glaziers, shopfitters |
| Roof and gutter applications on metals | Neutral (oxime) cure prevents corrosion on Zincalume®, Colorbond®, and galvanised steel, extending the life of metal roofing systems. | Roofers, plumbers, metal fabricators |
| HVAC penetrations and air-conditioning duct seals | Forms a flexible, dust-proof gasket that withstands temperature variations (-50°C to 150°C), maintaining efficient air systems. | HVAC technicians, plumbers |
| Sealing ceramic tiles and vitreous enamel finishes | Bonds effectively to challenging non-porous surfaces, ensuring a reliable, waterproof seal in wet areas. | Tilers, builders |
Ensure joint flanks are sound, dry and clean—free from dust, oils, release agents and moisture. For impervious substrates, use a fresh-cloth two-wipe solvent clean.
Wipe with a solvent-dampened lint-free cloth; immediately follow with a dry cloth. Replace cloths frequently. Suitable solvent: 100% white spirits.
Mask both edges tightly to control bead geometry and prevent edge smearing. Remove tape while sealant is still wet.
Adhesion tests are recommended. Prime where required and design the joint to move: 2:1 width:depth; max width 30 mm; max depth 15 mm; use backer rod where depth >10 mm.
50A for non-porous; Everflex Supaprime for porous. Apply thinly by brush and allow several minutes for solvent evaporation.
Insert closed-cell polyethylene rod approx. 25% larger than joint width to control depth and prevent three-sided adhesion.
Apply between +5 °C and +40 °C ambient. Cut nozzle at 45°; push-gun the bead with the nozzle contacting both flanks. Tool within ~5 minutes to compact the sealant and achieve a smooth finish.
Maintain a steady pace; keep the nozzle ahead of the bead to force sealant into the joint and wet both sides.
Lightly moisten a spatula and form a concave profile for maximum movement capability. Clean excess while wet.
WARNING: Causes skin irritation. May cause an allergic skin reaction. Causes serious eye irritation.
Wear protective gloves, protective clothing, eye protection (safety glasses with side shields or chemical goggles), and face protection. Use chemical protective gloves (e.g., PVC) and safety footwear (e.g., rubber gumboots). Contaminated work clothing must not leave the workplace. Remove and destroy contaminated leather items.
Use in a well-ventilated area. Local exhaust ventilation is usually required. Prevent concentration in hollows and sumps. Do not enter confined spaces until the atmosphere has been checked.
Store in original containers, securely sealed, in a cool, dry, well-ventilated area between 5°C and 30°C. Keep away from incompatible materials and foodstuffs. Protect containers from physical damage. Shelf life is 18-24 months in original packaging. Dispose of contents/container to an authorised hazardous or special waste collection point in accordance with local regulations.
Correct surface preparation and priming are critical for reliable adhesion and long-term joint performance. Improper prep leads to costly failures.
Surface prep: Surfaces must be sound, dry, and clean. Remove all dust, oils, grease, and contamination using the two-wipe process. Moisten a clean cloth with Acetone or 100% White Spirits for the first wipe, then follow with a dry, clean cloth to remove residues. Change cloths frequently.
Primer: Optional. An adhesion test is recommended. If priming is necessary, use Adheseal 50A for non-porous metals, applied with a small brush and allowed to dry for several minutes.
Surface prep: Ensure surfaces are sound, dry, and free of dust, oils, and grease. Use the two-wipe process with Acetone or 100% White Spirits, followed by a clean, dry cloth. Mask joint edges for a neater finish.
Primer: Optional. An adhesion test is recommended. If priming is necessary, use Adheseal 50A for non-porous surfaces, applied with a small brush and allowed to dry for several minutes.
Surface prep: Surfaces must be structurally sound, stable, dry, and free of dust, loose material, oils, grease, and curing compounds. Concrete must cure for at least 28 days before sealant application to prevent mould growth or adhesion failure. Substrate must be free from surface water and continual dampness.
Primer: Optional. An adhesion test is recommended. If priming is necessary, use Everflex Supaprime for porous substrates, applied with a small brush and allowed to dry for several minutes.
Surface prep: Surfaces must be sound, stable, dry, and clean, free of dust, loose material, oils, and grease. Remove any contaminants that may hinder adhesion.
Primer: Optional. An adhesion test is recommended. If priming is necessary, use Everflex Supaprime for porous timber, applied with a small brush and allowed to dry for several minutes.
| Property | Value |
|---|---|
| Product Type | Polysiloxanes |
| Curing System | Oxime |
| Density | 1.03 g/cm³ |
| Shore A Hardness | 25—30 |
| Elongation at Break (ISO 8339) | 600% |
| Application Temperature | 5°C to 40°C |
| Temperature Resistance | -50°C to 150°C |
| Movement Capability | ±50% |
| Elastic Recovery | >90% |
| Skin Time | Approximately 20 minutes |
| Cure Rate | 2mm per day at 25°C & 50% humidity |
Here are some common examples on where Adheseal N70 Industrial Silicone Sealant used by our customers.
