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05 / Cavity Barriers

Cavity barriers & access hatches.

Compartmentation only works if the lines are continuous. That means sealing cavities at every compartment junction and installing fire-rated access hatches to any panel that needs to be opened for maintenance.

Emergency sign
The Fundamentals

Why cavity barriers matter

Cavities exist in almost every building — behind cladding, above suspended ceilings, within partitions and in floor voids. Without barriers at compartment junctions, fire and smoke can travel freely through those concealed spaces and bypass fire-rated walls and floors entirely. Post-Grenfell, the industry's understanding of cavity barrier failure has sharpened considerably. Correct specification and correct installation are both non-negotiable.

Scope of Works

What we install

  • Open-state and closed-state cavity barriers to BS EN 1366-4
  • Thermally-activated cavity barriers for use behind cladding systems
  • Service-penetrating cavity barriers and closers
  • Cavity closers at window and door reveals
  • FD30, FD60, FD90 and FD120 fire-rated access hatches
  • Installation to manufacturer-approved details with photographic records
Access Hatches

Fire-rated access hatches

Any compartment line that needs to be opened for maintenance must have a fire-rated access hatch installed in place of a plain panel. We supply and fit hatches rated from FD30 to FD120 with self-closing mechanisms and intumescent edge seals, and record every hatch location as part of the compartmentation schedule.

Why Alpha Fire

What sets us apart

  • Cavity barriers integrated with fire stopping and compartmentation scope
  • Certified access hatches from approved manufacturers
  • Photographic installation records on every job
  • IFC / KIWA accreditation Nr 3039
Work with us

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