Movable partition systems including intumescent material and methods of controlling and directing intumescent material around the perimeter of a movable partition system

A movable partition system, comprising:

• a track assembly, comprising:
• at least one track comprising a first bottom surface separated from a second bottom surface by a gap disposed between the first bottom surface and the second bottom surface;
• and
• at least one shroud at least partially surrounding the at least one track;
• a movable partition engaged with and horizontally extendable along the track assembly;
• a first mass of intumescent material disposed between the first bottom surface of the at least one track and the at least one shroud on a first side of the gap;
• and
• a second mass of intumescent material disposed between the second bottom surface of the at least one track and the at least one shroud on a second, opposing side of the gap, the first mass of intumescent material and the second mass of intumescent material shaped and positioned to expand toward one another, contact one another, and form a seal therebetween extending along at least a portion of a periphery of the movable partition when the movable partition is exposed to fire, wherein
• the at least one shroud is configured to confine expansion of at least one of the first mass of intumescent material and the second mass of intumescent material into the gap between the first cup-shaped rail and the second cup-shaped rail.

A method of installing a movable partition system, comprising:

• positioning at least one mass of intumescent material to seal at least a section of a gap at a periphery of a movable partition when the at least one mass of intumescent material is exposed to fire;
• positioning at least one additional mass of intumescent material to contact the at least one mass of intumescent material at the gap at the periphery of the movable partition when the at least one additional mass of intumescent material is exposed to fire;
• and
• confining expansion of the at least one mass of intumescent material toward the at least one additional mass of intumescent material by sandwiching the at least one mass of intumescent material between a shroud and a bottom surface of a track configured to guide extension of the movable partition and confining expansion of the at least one additional mass of intumescent material toward the at least one mass of intumescent material.