Which set of elements is described as part of a fire-rated wall assembly?

• A. Steel studs, mineral wool insulation, and decorative finish
• B. Non-fire rated gypsum board; slab-to-slab partitions; fire-rated caulking at connections
• C. Fire-rated gypsum board; slab-to-slab partitions; standard caulking at connections
• D. Fire-rated gypsum board; slab-to-slab partitions; fire-rated caulking at connections

Answer: (D)

A fire-rated wall assembly is defined by components that maintain a fire barrier across the wall, preventing heat and flames from passing through. The essential elements are fire-rated gypsum board, which provides the rated resistance of the wall itself; slab-to-slab partitions, which ensure the barrier continues through the floor/ceiling interface; and fire-rated caulking at connections, which seals joints and penetrations so the fire barrier isn’t compromised by gaps. Using non-fire-rated gypsum board or standard (non-fire-rated) caulking would weaken the wall’s ability to resist fire, while the combination of fire-rated gypsum board, proper partitioning, and fire-rated caulking maintains the intended fire resistance.