My customer is creating a storage area that is high-hazard, high-piled combustible storage (Group A Plastic) that nearly qualifies for application of NFPA Chapter 13, Miscellaneous Storage.
However, the NFPA 13-2016 definition of Miscellaneous Storage includes the qualification, "...does not exceed 1000 sq. ft. in one area or pile,..." NFPA 13 is silent on how to calculate the area.
The IBC defines "High-piled Combustible Storage Area" as: "An area within a building that is designated, intended, proposed or actually used for high-piled combustible storage, including operating aisles." If I use the IBC definition it puts this area at 1650 sq ft.
What is the proper calculation of area as it applies to Miscellaneous Storage?
Submitted anonymously and posted for discussion. Discuss This | Submit Your Question | Subscribe
8/12/2020 10:52:00 am
High-piled storage areas are calculated using the footprint plus 15' on each side not against a wall. That is one pile or area. However, if multiple piles of this size exist, then the area is calculated as the aggregate of the piles. 2018 IFC §3204 and §3206.2.1 will assist in designating these. The definition of miscellaneous storage is a little more involved, however. The area must be incidental to the primary use of the building, and it must constitute less than 10% or 4,000 ft2 of the sprinklerd area, whichever is greater.
8/12/2020 11:06:20 am
The customer wants to qualify for Miscellaneous Storage. The NFPA definition of Miscellaneous Storage continues, "...does not exceed 1000 ft² in one pile or area and is separated from other storage areas by at least 25 ft." In this scenario, if the area perimeter encompasses only the footprints of the racks and all interior aisles the area is 982 ft². If the perimeter aisles required by the IBC are included the area is 1644 ft². Understandably the customer is keen on using his defined area. I hope the NFPA will provide a definition in future editions of "13."
8/12/2020 11:42:45 am
Miscelaneous storage needs to remain "miscelaneous".
8/12/2020 12:55:24 pm
If there is no separation on the higher hazard area you must extend the calculation 15ft surrounding the area in all directions to a minimum of 2,500sqft. for Extra Hazard .3gpm
8/13/2020 10:11:34 am
Thank you all for your comments. The folks on this blog have been an incredible resource. I agree with perspectives shared. I'm still unclear on how to measure the fire load (High-piled Combustible Storage Area). If the aggregate area is over 1000 ft² it will force the customer into Chapter 17 and the costs will rise. To sum it up: Do I include the perimeter aisles required in the IFC definition of High-pile Combustible Storage Area? Or do I shrink the area to include only the racks and interior aisles between the racks (since they are less than 25 feet away from each other)? The NFPA 13 doesn't provide clarity.
Leave a Reply.
Subscribe and learn something new each day:
Top May 2023 Contributors
Get 100 Days of Free Sample Questions right to you!
PE PREP SERIES