Adheseal N70 Industrial Silicone Sealant

Adheseal N70 Industrial Silicone Sealant is a neutral-cure, high-movement silicone for industrial sealing, window perimeters, general glazing, weathersealing, expansion joints and exterior construction joints. With ±50% movement capability and 600% elongation at break, N70 is designed for demanding joints that need to remain flexible through substantial expansion, contraction and outdoor exposure.

N70 has a broader role than a dedicated glazing silicone. It can weatherseal around windows, doors and curtain walls, while also covering concrete and masonry joints, HVAC penetrations, roofing, gutters, skylights, solar installations, marine work and general industrial sealing.

High-movement silicone for window perimeters and industrial joints

N70 is particularly useful where a neutral-cure silicone needs to accommodate large joint movement across mixed construction materials. It is suitable for perimeter sealing around mechanically fixed windows and doors, curtain wall weatherseals and general glazing, as well as expansion and control joints in concrete and masonry.

Why choose N70?

• ±50% movement capability: designed for highly dynamic expansion, control and perimeter joints.
• 600% elongation at break: provides substantial stretch before rupture.
• Greater than 90% elastic recovery: helps the cured seal return after extension or compression.
• Neutral oxime cure: non-corrosive to galvanised and zinc-coated steel and suitable for many common construction materials.
• Industrial-grade versatility: covers glazing, construction, HVAC, roofing, marine and manufacturing applications.
• UV stable and colour-fast: suited to long-term exterior exposure.
• Service temperature: -50°C to +150°C after cure.
• Matt grey finish: suited to many industrial and façade joint details.

Compatible substrates

N70 adheres to a wide range of construction and industrial substrates including glass, fibreglass, glazed and unglazed ceramic tiles, porcelain, vitreous enamel, concrete, masonry, timber, PVC and other compatible plastics, laminated surfaces and common metals including Zincalume, Colorbond, galvanised steel, stainless steel and aluminium.

Always confirm adhesion on variable coatings, plastics and sensitive materials before installation.

Window, glazing and weatherseal applications

For windows and façade work, N70 can be used as a flexible perimeter weatherseal around mechanically fixed windows, doors and curtain wall systems. Its ±50% movement capability makes it useful where frame movement, thermal cycling and exterior exposure are significant.

N70 is not a structural glazing silicone. It seals glazing and perimeter joints, but it should not be used where the silicone itself is required to structurally retain the glass.

Joint design and application

Surfaces must be structurally sound, stable, dry and free from dust, oil, grease, curing compounds and surface water. Concrete should cure for at least 28 days before application.

Where possible, design movement joints at approximately a 2:1 width-to-depth ratio. Internal joints require a minimum width and depth of 5 mm, while external joints should be at least 10 mm wide. Maximum joint width is 30 mm and maximum depth is 15 mm. Use correctly sized backing rod on deeper joints to control depth and prevent three-sided adhesion.

Apply between 5°C and 40°C and tool the joint before the silicone skins. Uncured material can be cleaned with white spirit or isopropyl alcohol; cured silicone must be removed mechanically.

N70 vs DOWSIL 791

Choose N70 when you need a broad industrial neutral-cure silicone with very high movement capability across glazing, construction, HVAC, roofing and mixed-material joints.

Choose DOWSIL 791 when the application is specifically an architectural curtain wall, façade or glazing weatherseal and the project calls for a dedicated premium weatherproofing silicone.

Important limitations

• Do not use in totally confined spaces.
• Do not apply underwater. Below-waterline use after full cure requires project-specific confirmation.
• Do not use for structural glazing, aquarium manufacture or mirror bonding.
• Do not use on polycarbonate sheeting.
• Do not paint cured N70.
• Composite panels require compatibility testing before use.
• Stain-test natural stone before use.
• Copper and brass may discolour.

Compare other glazing and perimeter options in our Window, Shopfront & Perimeter Weatherseal range.