sprinklernotes
Protection of Lateral Standpipes
You have asked the following question: "An AHJ is requiring the horizontal piping as the standpipe bulk main from one stairwell vestibule to another to be enclosed in 2-hour protection in a fully sprinklered building. Per IBC 905.4.1, is this piping considered lateral?" In response to your question, we have reviewed NFPA 14, 2016 edition as the applicable standard as well as the 2015 edition of the International Building Code (IBC). Our informal interpretation is that this is lateral pipe and that protection is not required. Section 905.4.1 Protection states, "Risers and laterals of Class I standpipe systems not located within an interior exit stairway shall be protected by a degree of fire resistance equal to that required for vertical enclosures in the building in which they are located." The exception provided under this section is very clear that in buildings equipped throughout with an approved automatic sprinkler system, laterals that are not located within an interior exit stairway are not required to be enclosed within fire-resistance-rated construction. The sprinkler system will minimize the potential for damage to the standpipe system. On a side note, laterals are not required to be protected in a non-rated enclosure such as an open parking garage. The protection for the vertical standpipe riser in the stairway must be the same as that for the laterals (with the exception of a building sprinklered throughout). If the stairway is not required to be in a rated enclosure, then the lateral piping is not required to be in rated protection either. A local written amendment has to exist to remove the exception of Section 905.4.1 to require protection of the laterals. NFPA 14 aligns with the requirements of the IBC. Section 6.1.2.1 says that standpipe system piping shall be protected from mechanical damage and fire damage in accordance with this section. Following that, the standard says the standpipe systems shall be protected in accordance with Table 6.1.2.2. Note that Table 6.1.2.2 refers to either a horizontal standpipe or "the horizontal portion of any standpipe" such as a feed main. The feed main is an example and not the only example. It can be the horizontal portion of any standpipe.
