Rockwood 18BFB Bottom Fire Bolt | For 3-Hour Fire Rated Metal Doors

The Rockwood 18BFB Bottom Fire Bolt is an essential life-safety component engineered to secure the inactive leaf of a pair of hollow metal fire doors. This heat-activated bolt allows you to eliminate the bottom automatic flush bolt and the associated dust-proof strike, significantly reducing floor maintenance and installation labor. Crafted from high-grade stainless steel, it ensures your fire-rated openings meet the most stringent 3-hour (A Label) building codes.

Precision Fire Protection & Code Compliance

• Heat-Activated Security: Engineered to activate when temperatures reach 230°F, the internal plug and gray plastic cover melt, allowing the bolt to project and lock the door leaves together to prevent fire and smoke spread.
  
• Barrier-Free Floor Design: By eliminating the bottom flush bolt and floor strike, you create a smooth, tripping-hazard-free transition that is ideal for hospitals, schools, and high-traffic commercial corridors.
• Maximum Fire Rating: UL Listed for up to and including 3-hour fire-rated openings when used in conjunction with a Rockwood 2840 or 2805 automatic top bolt on metal doors up to 4' x 8'.
  
• Durable Stainless Steel: The US32D Satin Stainless Steel finish provides superior corrosion resistance while matching the aesthetic of other architectural hardware.
  

Technical Specifications

• Model: Rockwood 18BFB
• Material: Stainless Steel (US32D)
• Bolt Size: 13/16" x 1-9/16"
  
• Plug Diameter: 1-7/32"
  
• Activation Temp: 230°F
  
• Required Components: Must be used with an automatic top bolt (Rockwood 2840 or 2805) for UL compliance.

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