I have a system where I am using a steel duct to penetrate a 0.5 hour U400 corridor wall, and am wanting to use a firestop system to protect the penetration per IBC 717.5.4 exception 1. the current design has the duct terminating to a wall register (I understand this is not allowed per exception 3.5 of the same code section but it is not clear for exception 1); does terminating to a wall register violate the system instruction for the duct to be rigidly supported on both sides? Am I otherwise incorrect in my assumption that this constitutes a through-penetration, and is in fact a membrane penetration? I am looking at system no. W-L-7143 as example.
Hello,
Thank you for reaching out to the Hilti Fire Protection Design Team to assist you with your firestop engineering needs.
We do not have a listed system for a duct membrane penetration; however, we can address your application through an Engineering Judgment, which will be a custom detail showing your exact application with the firestop components required to maintain the stated ratings.
Hilti is proud to announce the launch of our engineering website, the HILTI CONSTRUCTION PLATFORM (HCP). This platform will be the home for all of your Fire Protection Engineering needs, including Engineering Judgment requests. You can find more information on how to access this new platform here: https://www.hilti.com/ej (US) or https://www.hilti.ca/ej (Canada.)
If you have any questions, please reach out to our customer service team at 1-800-879-8000 (US) or 1-800-363-4458 (Canada) for assistance.
Thank you,
Zach Rezazadeh
Fire Protection Engineer