What is the purpose of fire stopping and firestop assemblies?

• A. To maintain fire resistance by sealing penetrations and joints through fire-resistance-rated walls and floors.
• B. To improve acoustic insulation.
• C. To reduce construction cost.
• D. To prevent water intrusion only outside.

Answer: (A)

Fire stopping and firestop assemblies are used to preserve the fire-resistance rating of fire barriers by sealing openings and joints in fire-resistance‑rated walls and floors. In a fire, penetrations for pipes, cables, and ducts, and joints where walls meet floors or ceilings, can create pathways for flames, heat, and smoke. The fire-stop system fills and seals these gaps with materials that resist heat and often expand to block the opening, maintaining the barrier’s integrity for the rated duration. This containment helps limit flame spread, smoke movement, and pressure differences between compartments, aiding life safety and property protection. While some products may offer other benefits, their primary role is to maintain the specified fire resistance, not to improve acoustics, reduce costs, or address water intrusion alone.