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Intumescent Fire Stop Manufacturing. Selling Internationally.

FIFS Fire Stop Product

Alva-Tech FIFS intumescent firestop foam sheet is an open cell, polyurethane based material with a polyethylene film on one side. On exposure to flame and heat, the material absorbs heat and begins to expand. Expansion begins between 350ºF and 400ºF with substantial expansion occurring above 450ºF. The flexible foam rapidly seals any existing openings and continues to expand up to 1000ºF. As the material expands in a confined area it will compact and form an insulating char to retard the spreading of flames and to control temperature increases.


This highly flexible soft foam has many applications. Due to its foam properties it can work well as a gasketing material when intumescence is required. Other possible applications might be as a covering, a cable wrap, fire door seals, through penetration boxes or enclosures containing communication cables or other items.

Physical Properties

DimensionsNominal 1/2″ thick (sheet size can vary)
Density (gr/cm3)N/A
Expansion Begins350ºF - 400ºF
Volume Expansion10 - 14X @500ºF

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