Flamebar Compact Fire-Rated Shafts
Increase Gross Leasable Area and
Reduce Construction Material Usage and Waste
Tall vertical compartments in buildings are called shafts, and are often used for stairways, elevators, MEP utilities, or dedicated for HVAC ductwork. Vertical shafts run through multiple floors, often from the lower floors to the roof, allowing for the vertical distribution of services throughout the building. Within residential buildings they are often near bathrooms and kitchens to streamline plumbing installations. In commercial structures, they are placed to serve large open floor areas effectively.
If the shaft connects four stories or more (penetrates three or more floor-ceiling assemblies), they are required to be fire-rated for 2 hours. Fire-rated vertical shafts contain and isolate fires to protect critical HVAC systems, plumbing, electrical conduits, and communication cables in buildings. Without fire-rated protection, vertical shafts can otherwise act as conduits for fire and smoke which may propagate to other parts of the building.
Fire-rated shafts maintain building structural stability and continuity during a fire event, preventing collapse and minimizing damage. Ensuring these shafts are fire-resistant is also essential for meeting codes and standards designed to safeguard lives and property.
Flamebar 2-Hour Fire-Rated Shaft Assemblies
Flamebar’s Compact Shaft assemblies use only one layer of drywall to enclose a vertical Flamebar riser to achieve 2-hour rated shaft performance. This approach integrates the performance of conventional assemblies into a much more compact assembly. Flamebar Compact Shafts provide HVAC and shaft functionality identical to conventional means.
Flamebar fire-rated shaft systems provide identical performance with less space and material, resulting in more gross leasable area (GLA) for adjacent rooms. This design accelerates construction schedules—minimizing small work material and waste and reducing the total number of required inspections. General contractors often report saving one full day per floor on a high-rise residential building!
Enhanced jobsite safety is also achieved with smaller floor openings, easier riser installation, and fewer inspections due to reduced number of material layers and removal of specialty drywall installation. The reduced use of specialty drywall means less waste and a better overall installation experience.
The benefits of our system include more efficient floor space utilization, faster installation times, integration of subduct connections to non-rated floor ductwork, and enhanced safety measures—making Flamebar the ideal choice for dedicated fire-rated shafts in modern construction.
FLAMEBAR COMPACT FIRE-RATED SHAFTS ARE EASY TO INSTALL
Flamebar is an easy-to-install system that comes in fabricated sections with an endothermic coating for quick onsite assembly. Flamebar compact fire-rated shafts:
- ASTM E119 and ASTM E814 tested and listed
- Reduce material usage, leading to less drywall waste
- Accelerate construction schedules
- Improve coordination of adjacent MEP utilities
- Lead to fewer, more accessible inspections
- Enhance jobsite safety with smaller floor openings
- Adheres to building and mechanical codes and standards
COMPACT SHAFT APPLICATIONS IN BUILDINGS
Flamebar fire-rated Compact Shafts are ideal for a variety of residential and commercial applications. Owners and developers appreciate the space-saving design and efficiency, while general contractors value the ease of installation and compliance with safety standards.
The compact design of Flamebar fire-rated shafts ensures they meet ventilation requirements while optimizing floor space and improving MEP coordination. Flamebar Compact Shafts are commonly used in hotels, condominiums, apartment buildings, and university dormitories. By integrating Flamebar fire-rated shafts into your building design, you gain a reliable and efficient solution for fire protection.
Subducts and Dampers in Exhaust Systems
Flamebar systems are compatible with subduct connections to non-rated horizontal ductwork, ensuring that the entire exhaust and ventilation system maintains its fire-rated integrity without the need for additional dampers, as permitted by code.
When a ventilation line penetrates the shaft and connects into an exhaust riser, subducts can be used to omit the need for dampers. A subduct connection is in effect a 22-inch snorkel turning up inside the exhaust riser at each horizontal connection. The snorkel design ensures proper exhaust flow and is allowed by code when continuous upward air is provided to provide the transmission of gasses between compartments.
This generally means that dampers must be omitted along the entirety of the ventilation line – even on upper mechanical floors – because the exhaust system needs to continue operating without interruption during a fire event. Subducts are installed within the exhaust riser behind the shaft wall and are designed to draw air upward and out of the building. This continuous upward air evacuates products of combustion through the exhaust line during a fire.
Who We Work With
Flamebar fire-rated HVAC systems benefit different team members throughout the construction process. Learn more below.
Engineers
Leading engineering firms in the US and worldwide simplify their designs by using Flamebar as their holistic fire-rated solution.
Mechanical / Sheet Metal
Flamebar simplifies the installation process, saving valuable project time.
General Contractors
Conquest delivers just-in-time (JIT) multi-hour fire resistive assemblies and ductwork directly to project sites
Owners / Developers
Flamebar replaces multiple disjointed materials with one holistic solution, resulting in a lower total install cost.
Case Study
Comcast Tower
Philadelphia, PA
The mechanical engineer working on the construction of Comcast Tower in Philadelphia, PA, developed a specification that required Type A and Type B testing. The project used Flamebar fire-rated ventilation systems for multiple applications, including the installation of Flamebar Compact Shaft.
FREQUENTLY ASKED QUESTIONS
Shaft enclosures in IBC-governed buildings generally require a fire-resistance rating of 1 or 2 hours, depending on building height and occupancy. The Flamebar Compact Shaft assembly provides a 2-hour fire-resistance rating tested to ASTM E119 under Intertek listing FIL-FMF 120-10, with a companion firestop at each floor penetration listed to ASTM E814 under FIL-FMF 120-09. Confirm the specific rating requirement for your project with your design team and local AHJ.
The Flamebar Compact Shaft reduces a conventional shaft wall assembly from 6 or more inches in width to approximately 2-1/4 inches. Instead of a conventional multi-layer framed-and-boarded shaft wall, the Compact Shaft uses Flamebar fire-rated duct plus a single layer of 5/8-inch Type X gypsum wallboard as a listed assembly component. The assembly is tested to ASTM E119 and ASTM E814 and is prescriptively compliant with IBC Sections 703.2.1.1 and 713.4.
Factory-built fire-rated shaft systems such as Flamebar offer several advantages over field-built shaft construction: listing integrity not dependent on field workmanship, a dramatically more compact assembly (approximately 2-1/4 inches versus 6 or more inches for conventional shaft walls in the Compact Shaft configuration), reduced multi-trade coordination, fewer inspection holds, and a fire-resistive coating applied under factory-controlled conditions.
Flamebar is a tested and listed factory-built fire-rated duct system. In the Compact Shaft configuration, one layer of 5/8-inch Type X gypsum wallboard is also required, and the 2-hour fire resistance of the assembly is enabled by the factory-applied BW11 endothermic coating on the Flamebar duct. Conventional gypsum shaft assemblies require multiple layers, framing, taping, and fire caulking across at least two trades. The Flamebar Compact Shaft replaces this with a single-trade installation and a single listed drywall layer.