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Thermal Cavity Barrier

Product 55


Thermal cavity barrier ideal for cavities around door and window apertures

Not available to purchase online.

We need to ask you a few more questions and ensure this is the suitable product for your needs.

To order please call us on +44 (0) 1 304 842 555


Thermal Cavity Barrier

An ideal solution where you require both fire and thermal protection, particularly cavities around window and door apertures. The waterproof barrier is completely water-resistant and offers over 1 hour of fire protection. Additionally, creating an effective thermal barrier between the cavity and window/door frame section. The Cavity Barrier comprises of a fireproof sponge fixed to a thin foil-faced intumescent strip. The system is completely moisture resistant.  Simply cut to the required length, subsequently using clout nails at 3 inches (75mm) centres to fix.

See the order reference tab for a full list of sizes available.

Cavity Barriers are pieces of fire-stopping material. They fit within the cavity of a building at each floor horizontally and party wall in a verticle position. The material provides compartmentation. Both the flames and heat cannot be transferred to other compartmental areas. Throughout the life of the building, the Cavity Barrier will remain fixed in place. In the event of a fire, the intumescent material expands and seals off the gaps. Additionally, the horizontal barriers allow for a ventilation gap within the cavity. Subsequently closing when the intumescent expands.

Our Cavity Barrier range at Envirograf® offers superb protection to your building by providing fire stopping. Explore the Cavity Barrier range online.


– Can be used in any cavity where both fire and thermal protection is required- Ideal for cavities around door and window apertures
– Easily fitted with ordinary clout nails, providing an economical and effective 1-hour fire barrier


– Tested to BS476 Part 20, achieving up to 66 minutes protection.


Order References / Sizes

ORDER REF                  Cavity Width                Foiled fixing               Sponge thickness

TCB/A                            50mm                          120mm                        30mm

TCB/B                            50mm                          150mm                        30mm

TCB/C                            80mm                          120mm                        30mm

TCB/D                            80mm                          150mm                        30mm

TCB/E                            100mm                        120mm                        30mm

TCB/F                            100mm                        150mm                        30mm