On a multi-famliy 4 story wood framed building (R-2) Type VA Construction, we would like to use th F-C-7086 detail in order to bring a 4" dryer duct up into the UL556 ceiling floor assembly, however we are told that the F-C-7086 or applies at the membrane penetration and does not address the issue as noted in ICC 717.6.2 for non-dampered shafts that enter (not transveres) a ceiling floor assembly. Therefore the local code official is advising that we must install fire wrap on all dryer vent duct in the UL556 assembly. Please advise if F-C-7086 supercedes this idea.
Greetings Brennan,
Thank you for using ASK Hilti!
The purpose of F-C-7086 is to prevent the spread of flame through opening around the non-dampered duct in accordance with UL 1479. For your reference, we have attached the UL 1479 Guide Info that explains how our firestop systems are tested and their purpose.
Regarding the code language and whether a damper or fire wrap is required on your project, the local code official or Authority Having Jurisdiction will need to make that determination.
We hope this helps. If you have any further 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 for choosing Hilti as your firestop experts!
Best Regards,
Ryan Kolodetsky
Fire Protection Engineering Team
