What type of firestopping technology expands significantly in volume when exposed to heat?

Intumescent firestopping technology is designed to expand significantly in volume when subjected to heat. This characteristic is crucial for its function in fire safety. When exposed to high temperatures, intumescent materials swell, forming a thick char that seals openings and gaps, thereby preventing the spread of fire and smoke through walls, floors, and ceilings. This expanding property enhances the material's ability to create an effective barrier against flames, making it particularly useful in environments where fire containment is essential.

The effectiveness of intumescent materials lies in their ability to respond dynamically to fire conditions. As temperatures rise during a fire event, these materials react by expanding and increasing in density, which helps maintain the integrity of the inactive spaces in the structure.

In contrast, mechanical, cementitious, and fibrous firestopping technologies do not exhibit the same expansive properties under heat. Mechanical systems rely on physical barriers or devices to inhibit fire spread, cementitious materials provide a protective barrier through their hard and durable structure, and fibrous materials are often used for soundproofing or thermal insulation rather than as a primary method to control fire spread. Thus, the unique property of intumescent materials of expanding in volume when exposed to heat sets them apart as an effective firestopping solution