FAQ Fire Penetration Sealing.
The modern approach to minimising the risk of fire damage is to compartmentalise buildings. In order to achieve this all walls, floors, ceilings and doors of a “compartment” must be able to resist the fire passing through them for anywhere up to 120 minutes. The intention is that during this time the building can be evacuated and the fire can be brought under control.
Since at least some service pipe and ductwork must inevitably pass through the fire resistant walls or floors it is necessary to ensure that the fire cannot spread at these points. The process of stopping fire spread at these points is known as fire penetration sealing or “fire stopping”.
How should I seal the penetrations caused by my pipes?
Several factors can influence this decision. Non-combustible, steel and copper, pipes do not burn and so the main objective when fire stopping non-combustible pipe penetrations is to seal any slight gaps between the pipe and the wall and to ensure that the pipe does not heat up to a degree that secondary combustion is caused on the non-fire side of the wall.
Combustible, MDPE, PVC and ABS pipes melt away in the event of a fire leaving an empty gap in the wall where the pipe once was. Fire can easily move through this gap unless an intumescent fire seal has been applied which can expand to close the gap. As with non-combustible pipe, insulation is still required on the non-fire side of the wall in order to prevent the pipe surface heating to such a degree that secondary combustion results.
Intumescent fire collars, mastics and tapes are available which can be wrapped around the insulation as it passes through the wall. These should always be used wherever combustible pipe passes through fire walls or floors.
I have a non-combustible copper/steel pipe – which fire sealing product is recommended?
Kaiflex ST and Kaiflex KKplus have both been tested on non-combustible pipe in combination with fire resistant wall constructions and shown to give in excess of 90 minutes protection against fire spread - dependent upon the diameter of the pipe.
Kaiflex PyroStar has been tested on non-combustible pipe in combination with fire resistant wall constructions and has been tested and shown to give up to 120 minutes protection. Please see the technical literature for more information on which pipe sizes have been tested in combination with different wall and floor constructions.
I have a combustible MDPE/ABS/PVC pipe – which fire sealing product is recommended?
Kaiflex PyroStar contains a powerful intumescent additive and expands rapidly in the event of a fire - crushing a non-combustible pipe. Independent testing has shown that Kaiflex PyroStar, applied around Kaiflex insulation, gives up to 120 minutes protection.
Please see the technical literature for more information on which pipe sizes have been tested in combination with different wall and floor constructions.