Mode of action and application

Under the influence of fire and radiant heat Interdens® and Exterdens® fire protection products expand to a multiple of their original volume forming a highly heat-insulating foam layer. Joints, cavities and other openings are closed, preventing or delaying the spread of flames and fumes effectively. Areas lying underneath the heat-insulating foam layer will effectively be protected from the impact of fire and heat.
The application areas of the intumescent Wolman products Interdens® and Exterdens® are widespread. They are incorporated in diverse fire-rated building components and used in many different structural fire protection applications. While strips are used especially for sealing the edges of building components, joints and cavities, sheets, rolls and punched parts enable the surface areas of building components and materials to be protected.

Applications in which Interdens® and Exterdens® products are used include:

- Fire doors and gates
- Windows and glazing
- Partition walls, ceilings and floors
- Security cabinets and safes
- Ventilation systems
- Tube/ pipe sealing
- Wiring and cable ducts
- Facades
- and many more

For application examples, click here:
Application examples: fire protection door (pdf)
Application examples: ventilated facade (pdf)

For further information on our products, a detailed discussion of your specific needs and for supporting you in finding the optimum solution for your application please consult our Technical service.


Expansion test with Exterdens - before / after exposure to fire

Picture: Odice S.A.S., F-Marly