I’ve had a few questions about the locking of stairwell doors lately, so it’s time for a quick update. There is more in-depth information about stairwell reentry in this Decoded article, and the basics are covered in this whiteboard animation video.
Keep in mind that when I talk about locking a stair door, I am referring to the stair side of the door – not the egress side of the door leading into the stairs. Here are some frequently-asked questions…
Q: Are all stairwell doors required to unlock automatically upon fire alarm?
A: NFPA 101 – Life Safety Code allows stairs serving 4 stories or less to be mechanically locked, and includes provisions for “selected reentry” (locking some doors mechanically and allowing reentry at other doors). NFPA 101 also exempts doors in some occupancy classifications from the stairwell reentry requirements. When stair doors are unlocked electrically, NFPA 101 requires the doors to be automatically released upon activation of the building’s fire alarm system.
The International Building Code (IBC) contains different requirements for stairwell reentry; mechanical locks are not allowed on stair doors regardless of the number of stories, “selected reentry” is not allowed, and the requirements apply regardless of the use group (except maybe detention and correctional facilities). For doors that are locked on the stair side, the IBC requires the locks to be “capable of being unlocked simultaneously without unlatching upon a signal from the fire command center, if present, or a signal by emergency personnel from a single location inside the main entrance to the building.”
Q: The IBC includes requirements for stairs serving 4 stories or less, and for high-rise buildings. What are the requirements if I have a stair serving more than 4 stories, but the building is not a high rise?
A: I wrote about this “loophole” in the IBC in a previous blog post, and a code change proposal was submitted for the 2018 edition of the IBC to address this. The proposal (E 74-15) was approved, and the 2018 edition of the IBC will be changed to clarify the requirements. In brief, stair doors in a building that is not a high-rise will require remote unlocking as described in the answer above. For high-rise buildings, the locks are required to operate the same way, but a two-way communication system is also required. I know of several situations where the upcoming change has been used as justification for a code modification on projects currently under construction.
Q: How do I know whether to follow the requirements of NFPA 101 or the IBC?
A: This will depend on the code that has been adopted and is being enforced in a project’s jurisdiction. If both codes apply (for example the IBC as the building code and NFPA 1/101 as the fire code), typically the most stringent requirements are used, which would be the IBC requirements. Many years ago I was called by a fire marshal who was enforcing the NFPA requirements and wanted to know how he could mandate the removal of mechanical locks on a 3-story stair. The fire code he was enforcing allowed mechanical locks in that situation, so I told him to call the building inspector who was enforcing a building code that did not allow mechanical locks on stair doors. They worked together to require the locks to be removed or changed to electrified locks that could be remotely released. The only project I have worked on where selected reentry was allowed, was a federal project where the GSA chose to use the NFPA requirements even though the building code requirements were more stringent. This practice is not common.
Q. Are locks on stair doors required to be hard-wired locks which unlock upon power failure?
A. Traditionally, fail-safe hard-wired locks have been used for stairwell reentry applications, but neither of the model codes specifically require fail-safe locks, or require locks on stair doors to unlock upon loss of power. If there was another way to safely and reliably unlock stair doors, the model codes do not prohibit it, but the AHJ may have some questions or may determine that the product is not acceptable. The locks would have to be capable of remote release – either from the fire alarm system or the fire command center.
Q. Is the stair discharge door also required to unlock remotely?
A. The stair discharge door is the door that typically swings out of the stairs and leads to the exit discharge (see photo above). NFPA 1o1 addresses re-entry from the stair enclosure to the interior of the building, but does not require the stair discharge door to unlock and allow access into the stairwell. The IBC specifically exempts the discharge door from the reentry requirements, stating: “Stairway discharge doors shall be openable from the egress side and shall only be locked from the opposite side.” There may be a local requirement that applies to stair discharge doors, but I have not seen one (yet).
Q. Could I use passage sets and avoid all of this confusion?
A. Yes! Passage sets are fine, as long as the building owner does not require security between the stairs and the tenant floors. In some cases where passage sets were originally installed, mechanical locks were incorrectly retrofitted later.