Waterproof and fire-resistant double-sided PVC foam adhesive – Norseal 2521

      Norseal 2521: Flame-retardant PVC foam for sealing use

Norseal 2521 is a soft closed-cell PVC foam with single-sided acrylic adhesive, designed to provide waterproof and airtight sealing in industrial assemblies.

Its flame-retardant formulation, compliant with DIN 4102 (B1 depending on system), makes it suitable for environments where fire behaviour is critical, such as building applications, HVAC systems, and metal assemblies.

Thanks to its low compression force, the foam adapts easily to surface irregularities without deforming thin substrates (aluminium, steel or plastics). The closed-cell structure ensures excellent sealing once compressed, with stable ageing performance even in humid environments.

Key benefits

• Flame-retardant PVC foam designed to reduce flame propagation

• Closed-cell structure providing long-lasting waterproof and airtight sealing

• Low-compression foam ideal for thin or sensitive materials

• High conformability on irregular or uneven surfaces

• Available in multiple thicknesses and custom-cut formats

      Applications

✔ Partitions & panels

Norseal 2521 is used as a sealing gasket between panels or partitions. Its soft PVC foam fills gaps and compensates irregularities, creating a reliable barrier against air and humidity with minimal compression.

✔ Doors & windows

Ideal for peripheral sealing on frames. The foam adapts to manufacturing tolerances and provides durable water and air tightness, while its low compression avoids deforming thin aluminium, steel or PVC profiles.

✔ HVAC – ventilation & air-conditioning

Perfect for sealing around ducts, housings and air-handling units. It reduces air leakage, improves system efficiency, and its flame-retardant formulation adds safety within ventilation networks.

✔ Refrigeration

The closed-cell foam prevents moisture absorption, making it suitable for cold rooms, refrigerated doors, hatches and insulated panels, maintaining stable sealing despite temperature variations.

✔ Metal roofing systems

Used under ribbed sheets or between roof and cladding components, it compensates metal sheet irregularities and ensures effective sealing against air, water and dust.

✔ Appliances & equipment

Works as a soft gasket or anti-squeak foam in covers, panels and access doors. Its low compression avoids stressing lightweight parts while enhancing acoustic comfort.

      Why choose Norseal 2521?

Norseal 2521 is the right solution when a project requires a reliable sealing foam that compresses easily while maintaining a durable barrier against air, water and moisture. Its closed-cell PVC structure ensures consistent performance even on irregular surfaces or assemblies with dimensional tolerances.

Its flame-retardant formulation makes it suitable for applications subject to fire-safety constraints, including building construction, HVAC systems, metal roofing, and sandwich panels.
The acrylic adhesive enables quick installation and long-term bonding stability.

Available in several thicknesses and custom-cut formats, Norseal 2521 can be sized precisely to fit your technical requirements.

      Technical data