Are fire dampers required at 1-hr shaft walls?
Are fire dampers required at 1-hr shaft walls?
(OP)
I could use a bit of help trying to understand the code requirement for fire dampers at shaft walls. I was reviewing a building air system design that includes a duct riser that extends from the roof down three floors. The shaft wall is noted as 1-hour rating (as expected). I understand in a fully sprinklered building, ducts that penetrate 1-hour walls do not require smoke dampers. Is the same true for shaft walls? I looked through NFPA 90A, but I could not seem to get a clear answer (the diagram does not provide any insight). Perhaps I am overlooking the obvious. Any assistance you can provide is greatly appreciated. Thank you.





RE: Are fire dampers required at 1-hr shaft walls?
RE: Are fire dampers required at 1-hr shaft walls?
RE: Are fire dampers required at 1-hr shaft walls?
Under the International building Code, a sprinkler system may eliminate many dampers. However your local Authority having jurisdiction may not agree.
RE: Are fire dampers required at 1-hr shaft walls?
I read the following two items in 90A that appear to conflict with each other:
"Approved fire dampers shall be provided where air ducts penetrate...rating of 2 hours or more"
"Fire dampers shall be installed at each direct or ducted opening into or out of enclosures required by 3-3.4.1." The referenced section includes 1-hr construction.
Thanks again. I think I better understand it now.