By Austin Regan
It may be an understatement to say the Building Code is an imperfect document. Like any law, the Code had many interested parties with many different agendas. None of those parties got the exact document they wanted. In many cases certain sections of the Code were agreed to even though no one was happy with the final wording or meaning. It was felt by all that given the constraints they had to work under this was the best that could be done.
The point of the law dictating that the Code be updated every three years was to give everyone the opportunity to revisit some of these troubling sections. The hope was the experience of designing by and implementing some of these sections would lead the professionals to come up with ideas on how to fine tune requirements to make for better buildings.
Chapter 10’s section on Exit Discharge is a case in point. From the earliest Codes, the concept of safely egressing buildings always started with the premise that you were not safely discharged until you were outside the building. As buildings got vertical the concept of having two separate means of egress logically became the minimum that needed to be provided and those egress points had to be remote from each other for maximum safety.
The concept of having those remote exits discharge to the street ran up against the reality of Manhattan real estate practices where parcels were divide into deep lots with minimum frontage along the street and rear yards that were landlocked. The 1968 Code devoted a whole section to the concept of the Street Floor Lobby which allowed for at least 50% of the egress stairs to discharge into the building lobby as opposed to directly to the street.
The Street Floor Lobby does not exist in the 2008 Code or the new 2014 Code. However, the section of Chapter 10 that addresses exit discharge (Sec 1023 -2008, Sec 1027 -2014) created an exception that allowed the spirit of the Street Floor Lobby to live on. Fifty percent of stairs could still discharge through the lobby (protected area) under certain conditions. One of the conditions, however, proved to limit designers’ abilities to design their lobbies.
Section 1023.1 Exception 1.1 stated “Such protected area shall provide a free and unobstructed way to the exterior of the building, which way is readily visible and identifiable from the point of termination of the exit enclosure.” This basically meant that as soon as you opened the stair door you needed to be able to immediately see the exterior doors. This became extremely difficult to achieve in many instances and the committee wanted to find a way to make the section more flexible. All parties agreed that as long as the path through the lobby was clearly marked with exit signs, safety was not being compromised.
While the committee knew what it wanted to achieve, coming up with the actual language to get to that goal proved to be difficult. Restrictions to the number of turns along the path to the exterior or introducing another travel distance limitation were discussed and discarded. The final language of Section 1027.1 Exception 1.1 appears as follows “Such protected area shall provide a free and unobstructed path of travel to an exterior exit door and such exit is readily visible and identifiable within 40 feet from the point of termination of the exit enclosure.”
The 40 foot number was not arbitrary. Figuring that your average length of a stair core was approximately 20 feet it was decided that doubling that number would allow a stair door to open outside the general lobby area while a user would have a relatively short distance to get around the core and be in the lobby proper where the exterior doors could be seen.
This was an example of a small change but one that can be a huge help to designers while keeping users safe. It is also a great example why the formal updating of the Code on a regular basis is so important.