Tenmat’s NVFB Non-Ventilated Cavity Fire Barriers, are manufactured from stone mineral wool with an A1 Reaction to Fire Rating and are designed to maintain fire resisting performance to external wall cavities.

The NVFB is capable of providing effective fire resistance, for integrity (E) and insulation (I) for up to 120 minutes (EI120) depending upon the orientation of the NVFB and the construction of the external walls.

Tenmat NVFB is supplied cut to size to suit the cavity width or can be supplied in full slabs. It is supplied as plain stone mineral wool as standard and can also be supplied with foil encapsulation or with an integral DPC.

The NVFB is designed for use within cavities up to 600mm wide and only requires 5mm of compression when fitting.


Tenmat’s Non-Ventilated Fire Barrier (NVFB-LD) is a full fill cavity fire barrier manufactured from a Euroclass A1 Reaction to Fire classified 100mm thick low density stone wool. The product is installed between the inner and outer substrates of a masonry façade to reinstate the fire resistance performance of the cavity. The lighter density allows greater scope for compression when installing within brickwork cavities when using wet mortar.

Cassette Infill

For cassette panel applications the Tenmat Cassette Infill can be supplied. This is an A1 non-combustible stone wool insert designed and tested to be used to fill out the depth of the cassette panel, allowing a continuous air gap to be maintained behind the cassette panel without the need for notching around the panel joints. See the Technical Data Sheet, linked on this page.

NVFB Sizes:

Cut to Size:
100mm Deep x Width to suit cavity (+5mm for compression fit) x 1000mm

Full Slabs:
100mm x 605mm x 1003mm (available plain or foiled)
100mm x 1000mm x 1200mm (available plain only)
Non-standard 82mm thickness available upon request.

  • Cavity Fire Barrier for use at: Compartment Floor, Compartment/
  • Party Walls & Around Openings
  • CCPI Verified
  • UL-EU 3rd Party Certification
  • Fire Resistance Classification to EN 13501-2
  • A1 Reaction to Fire
  • Fire Rated up to 120 minutes integrity and insulation (EI120)
  • Suitable for cavities up to 600mm
  • Suitable for use vertically and horizontally
  • Tested for use in conjunction with masonry support brackets
  • Tested with SFS Systems with calcium silicate fibre cement boards
  • Provided in 1 metre lengths
  • Standard thickness/depth of 100mm
  • Available in a reduced thickness/depth of 82mm
  • Optional integral DPC to prevent moisture migration
  • Supplied plain as standard. Optional foil encapsulation available
  • No maintenance required after installation

Previous versions of product information are available upon request.


For more information, to order or speak to a member of our product team

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