Fire-rated joints and penetrations

Intumescent acrylic for fire-rated joints, door frames and pipe and cable gaps, rated up to 4 hours to BS 476 Part 20.

What matters here

A fire-rated joint has to hold back fire and smoke for as long as the wall or floor around it. That rating comes from a fire test of a complete seal: the wall or floor, the gap width, the backing rod and the depth of sealant. Build the joint the way it was tested and it carries the tested rating.

Which Pereseal to use

Pereseal FR is an intumescent acrylic firestop sealant. At about 180 °C it chars and expands two to three times, closing the gap. Warringtonfire tested it in linear gap seals in concrete walls and floors to BS 476 Part 20:1987 (report WARRES No. 181672), with integrity up to 240 minutes. A 10 mm gap sealed 10 mm deep over polyethylene backing rod reached 240 minutes for both integrity and insulation.

It's rated for horizontal and vertical joints and takes joints up to 50 mm wide. Use it for perimeter pointing of fire doors and window frames, duct systems, fire walls and partitions, and gaps around pipes and cables. The test report is in the technical library.

On site

Fit the backing rod at the depth the report shows, gun in the sealant and tool it with a damp spatula. Keep it away from water for 24 hours. Paint over it once cured if the finish calls for it.

Questions to ask

What rating does the wall or floor need?: Pereseal FR reached integrity of up to 240 minutes (4 hours) to BS 476 Part 20. Pick the tested seal that meets the required period.
How wide and deep is the gap?: FR takes joints from 5 mm up to 50 mm wide. Match width, sealant depth and backing rod to the tested seal.
Is it a wall or a floor?: Both were tested, and each has its own results in the report. Use the seal tested in your orientation.
Is it a joint or a service penetration?: FR seals linear joints and the gaps around pipes and cables. Send us the pipe or cable type and size and we'll help with the detail.