PROJECT
building technology
Elevator hoistway closures that use semitransparent film effectively seal hoistway openings to prevent smoke migration during a fire, allow for through-passage of car occupants, and reseal the opening if accessed during an alarm.
shall be provided in accordance with Section 3007, “Fire Service Access Elevators.” Each FSAE shall also have a capacity of not less than 3,500 lb. and shall comply with Section 3002.4 [Elevator car to accommodate ambulance stretcher]. Similar to evacuation elevators, FSAEs must be in a ‘hardened’ shaft with a one-hour fire-resistance rating to four stories and two-hour rating above four stories. FSAEs are also required to have an elevator lobby from the second floor up as long as the floor of discharge is sprinklered. Therefore, hoistway seals are not required in 2015 IBC 709.4.2, “Smoke-barrier Walls Enclosing Areas of Refuge or Elevator Lobbies,” within FSAE lobbies. Recent changes in fire and building codes are a direct result of the door industry looking to help solve the fire problem in high-rise buildings by employing innovative products ings. As a result, using these products in lieu of constructing elevator lobbies has become
at elevator openings. The resulting win-win for designers and building owners is more
popular in the design community.
cost-effective choices in the use of space once reserved for elevator lobbies. CA
“Newer sliding-type fire doors complying with smoke and draft requirements are frequently allowed as an alternative to building lobbies,” said Dawdy. “In some applications, accordion-type doors are employed to seal banks of hoistways. Rolling steel fire doors are specifically not allowed. However, they may be used in lobby designs that also include listed swing doors, providing personal egress,” he added. Modern elevator hoistway closures range from semitransparent-film type to woven, coated fiberglass materials. The design intent is to seal hoistway openings to prevent smoke
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migration during a fire, allow through-passage of car occupants, and reseal the opening if
Circle 5 on the Reader Service Card.
National Fire Protection Association (NFPA), nfpa.org
accessed during an alarm.
CornellCookson LLC, cornelliron.com
International Code Council (ICC), iccsafe.org
DIFFERENT ELEVATORS, STANDARDS
Public-passenger elevators are installed to serve all floors of a building or may have separate banks targeting exclusive floors, which requires multiple lobbies to protect the hoistway from the migration of smoke and other combustion products. “Public elevators are a good target for hoistway closures since they eliminate the construction of elevator lobbies throughout the building,” explained Dawdy. “This is a significant savings for residential and commercial buildings that have elevators targeting exclusive floors. When public elevators need to be used for emergency evacuation, hoistway smoke closures are still appropriate, based on 2015 IBC Section 713.14.1, “Elevator, Dumbwaiter and Other Hoistways,” which states “Enclosed elevator lobbies are not required where additional doors are provided at the hoistway opening…when tested in accordance with UL 1784 without an artificial bottom seal.” There are some IBC codes and sections architects and designers must be aware of, including Section 403.6.2, “Occupant Evacuation Elevators” that states, “Where installed in accordance with Section 3008, passenger elevators for general public use shall be permitted to be used for occupant self-evacuation. Where elevators are to be used for occupant self-evacuation during fires, all passenger elevators for general public use shall comply with Section 3008 (10 sections).” “Since these types of elevators are intended to be occupant operated during evacuation periods, they must be in a ‘hardened’ shaft with a one-hour fire-resistance rating up to four stories and two-hour rating above four stories,” explained Dawdy. “Additionally, occupant evacuation elevators require lobbies at all floors except the level of discharge, meaning there is no code provision for hoistway closures,” he added. Unlike public-passenger and occupant-evacuation elevators, fire-service access elevators (FSAEs) provide a capable and durable hoistway with the ability to operate for extended periods of time during a fire to aid fire fighters and emergency responders. FSAEs must serve all floors. In buildings with an occupied floor more than 120 ft. above the lowest level of fire department vehicle access, no fewer than two FSAEs—or all elevators, whichever is less— CIRCLE 213
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