Fire Block

Cavity Barriers

Doing everything possible to prevent a fire from being able to spread
within a building is an essential part of health and safety

Cavity Barriers​

A cavity barrier is a way of closing off concealed holes or gaps that exist within parts of a building such as its roofs, ceilings, walls and floors. These gaps are generally invisible to the eye once the building is completed, such as those between a wall and its external cladding. The cavity barriers are intended to seal up these gaps to prevent flames or smoke from being able to move along them and spread through a building that way

Fire Stops

As with a cavity barrier, a fire stop is a way of containing fire and smoke inside a building, which is why they are frequently assumed to be the same as each other. However, a fire stop usually involves creating the floors, ceilings and walls of a building out of a material that is resistant to fire, or of closing off the slim gaps that can be seen between its walls, floors and doors through which smoke and flames can escape and spread through a building.

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Differences in materials

Although they perform different roles in the passive fire protection process, there are some similarities in the materials that are used for cavity barriers and fire stops. For instance, intumescent materials can be employed for both of these fire safety procedures, but for cavity barriers, mastic seals are used as these expand in the heat and block the cavities. These seals can also be used for fire stopping, but so can passive fire protection coating for walls, ceilings and other surfaces such as intumescent paint for steel, which are not used as cavity barriers. Essentially the biggest difference between a cavity barrier and a fire stop is that the first is designed to seal internal gaps within walls, ceilings and other parts of a building. By contrast, fire stops are intended to seal visible, external gaps between them that are caused by imperfect fittings.

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A retrospectively installed cavity barrier system developed by leading fire protection experts.

Fire Block Ltd is pleased to announce we are now approved installers in the UK of the patented Injectaclad system.

Injectaclad is an acrylic based graphite sealant developed by leading fire protection experts. It is used to reinstate the fire resistance performance of wall and floor construction cavity details, where linear gaps are present within hidden voids that can allow fire and smoke to pass through from one compartment to another.

Injectaclad expands upon contact with heat and is considered as an intumescent or reactive material.

The product is pumped into the desired depth and width void using a patented method to form a linear cavity fire barrier utilising the systems reinforcing mesh and holding pin supports.

Passive Fire Protection

Based in the North West of England, we work Nationally and provide Free, No Obligation Quotations, no matter how small or large the project.

We are SideRise accredited and fully trained for the installation of cavity barriers. We have worked on major installations, both for Domestic Tower Blocks and commercial Office Towers, working on both Refurbishments and New Builds.

All of our works are reported using the BORIS system, giving both before and after photographs, and come with either BM Trada Certification (for Passive Fire Protection Cavity Barriers, Penetration Seals and Linear Seals) or FIRAS certification for Intumescent Paint or Boarding.