What is the Purpose of a Fire Cavity Barrier?

A fire cavity barrier is a form of passive fire protection that falls under the banner of compartmentation – which refers to the ability to restrict a fire to a specific section of a building to give people more time to escape the building and firefighters more chance of containing the fire and putting it out. In addition such methods, which also include fire-proof doors and firestops also help to protect the all-important escape routes. Passive fire protection is so-called because once installed it does not need any manual input to do its job. In order to gain access to the installation of and information as to the most suitable passive fire protection equipment it is best to seek out a local fire stopping contractor. These fire stopping contractors are experts in their field and are best placed to offer their expertise as to what you will need in your building.

What is a fire cavity barrier?

A fire cavity barrier, as mentioned is one element of a passive fire protection armoury used to separate void spaces in walls, over ceilings and under suspended floors. They are built out of fire-inhibiting materials such as glass fibre or cement mortar and are fitted within building cavities.

How do fire cavity barriers work?

Cavity barriers work by closing off concealed holes and gaps in the parts of the building outlined above. They seal off these gaps which prevents flames or smoke from being able to travel between important spaces and spread throughout the building. This helps restrict the movement of flames and smoke giving an all-important time boost for evacuation and firefighting, as well as stopping escape routes from becoming cut off.

The regulations

The fire cavity barrier regulations in housing are covered by BS 9991. This lays down guidance on the effective design, management and usage of residential buildings, making sure effective fire safety protocols are implemented. It covers both new buildings and extensions to existing properties. The regulations covered here dictate that buildings must have passive fire protection measures in place to control the spread of fires. Fire cavity barriers are probably the single most effective measure that exists to do this job, even working in hidden parts of the building to help inhibit the spread of flames and smoke. In terms of regulations dictating how fire cavity barriers should be used, we have ADBV2 which determines that fire cavity barriers should be situated:

  • at the junction between an external cavity wall (except when walls have two leaves of masonry or concrete with a minimum thickness of 75mm) and every compartment floor and compartment wall.
  • at the junction between an internal cavity wall (except when walls have two leaves of masonry or concrete with a minimum thickness of 75mm) and every compartment floor, compartment wall, or other wall or door assembly which forms a fire-resisting barrier.

 Fire cavity barriers are an extremely important part of fire safety in buildings and one that fire stopping contractors will always use to boost the fire safety profile of any new building or extension.