Which firestop system qualifies as an intumescent firestop?

Intumescent firestop systems expand when exposed to heat, forming a char that can seal gaps and prevent the passage of fire and smoke. Pillows are specifically designed to be placed in wall or floor penetrations and are made from materials that expand when heated, thereby filling voids and enhancing the firestop effectiveness. This characteristic makes pillows an ideal choice as intumescent firestops, as they actively respond to fire conditions to provide enhanced protection.

On the other hand, caulks, sealants, and foams may provide effective barriers against fire, but they don’t necessarily exhibit the same expansion properties as intumescent materials. While these options can be important components of firestop systems, they do not inherently expand in the same way under heat, thus differentiating them from intumescent firestop systems.