Expansion Joint Fire Barriers: Design Professional Information
Design Professional Considerations
Rigorous Third-Party Testing Requirements
- Dynamic Movement Cycle Testing
Evaluates performance under repeated movement at varying rates to challenge the system’s durability. This simulates an accelerated version of real-world building lifecycle and structural movement. - High-Temperature Fire Exposure
Subjects assemblies to temperatures up to 2,000°F for durations of 1, 2, 3, or 4 hours, testing both horizontal deck and vertical wall applications. - Hose Stream Test (Vertical Applications)
After fire exposure, a high-pressure hose stream is applied to assess the system’s ability to remain intact—replicating the impact of a firehose during actual firefighting conditions.
Tested Substrate Conditions
Fire-resistive joint systems are evaluated under multiple substrate conditions to reflect real-world building applications. Testing is conducted in both horizontal and vertical assemblies to verify performance across different structural configurations:
- Horizontal Assembly Testing:
Horizontal oven testing is performed on rated concrete deck assemblies to assess joint system performance under fire exposure in floor and roof conditions. - Vertical Assembly Testing:
Vertical oven testing is conducted on rated steel stud and gypsum wall partitions to evaluate performance within wall systems.
Cover Plates
Expansion joint systems often incorporate cover plates to accommodate architectural finishes while maintaining fire-resistance performance. These covers can be designed to meet both aesthetic and functional requirements, even in challenging conditions:
Fire-rated expansion joint systems are evaluated based on three key elements:
- A properly rated substrate
- A rated movement (joint) system
- A metal cover plate (when applicable)
A variety of cover plate designs are available to suit architectural needs while maintaining compliance, including solutions for tight or complex conditions. Cover plates, such as stainless steel (e.g., 2 mil thick foil), can be secured using continuous termination bars. These may be installed behind alternating cover types or positioned in front of the fire-resistive joint material. Many manufacturers include these configurations within their tested and listed systems (e.g., UL 2079), allowing designers and installers to meet code requirements without compromising design intent.
