Ceiling fire dampers

[norske35]

i have a fire rated ceiling in a noncombustible one family house
the ceiling assembly is 1 hr
Its a sheetrock ceiling with steel joist., the ul design number doesn't have any information on opening protection
i'm looking for guidance on how to ceiling connection from equipment below and where taps are made into to ceiling

 

[EnergyProfessional]

You will need to find a different UL number that includes an opening for a damper. if the one you found is not for a damper, it is not rated to have the 1-hr with a damper of any kind.
Probably best to talk to a damper manufacturer and they can point you to one that includes one of their dampers. Some of the UL tests were paid for by a damper manufacture and only will refer to their specific damper. So if your favorite manufacturer didn't do such test, you may have to find a different manufacturer that did.

I don't know if this applies to dampers at all. But fire protection manufacturers like Hilti also can create an "Engineering Judgment" for your specific situation without actual physical tests. That is based on their experience and based on a very similar already tested UL design. Again, I have no idea if that is an option for damper manufacturers at all.

 

[BenMacier]

What about intumescent collar at the ceiling interface?
This will do the job in case of fire.


* Finding a solution is great * Knowing how to implement it is fantastic * Believing it is the only one and best is naive ?

 

[norske35]

this is under nyc building code which is IBC as modified. The AHJ is not helpful
I have a plan from an architect for a noncombustible one family dwelling.
floors are 1 hr rated. the architect has not responded to me on ul detail. the only one on his plans is UL 524 which doesn't say anything
about openings
I looked at Ruskin, Greenheck CFD . they don't show connections to ductwork, mostly air connections from diffusers
there are CFD's for wood trusses that have a boot for ceiling duct transitions . but why not for combustible construction

the supply ductwork has to get from room into floor assembly branch distribution. according to code the membrane penetration needs a CFD
i was thinking a 1 hr duct fire wrap instead of cfd. problem joist run different directions , solid steel beams. fire wrap takes 2" of thickness over round duct.

another way is to line joist bay with fire code sheetrock. this is a problem with different joist runs parallel and perpendicular to duct run

then i go back to CFD .

 

[EnergyProfessional]

There is a chance what you are looking for doesn't exist (yet). I don't know residential, or NYC, but I'm surprised a single family home has rated ceilings. Is that from a garage?

I recently saw a Greenheck course about the application of radiant heat dampers (note, this is not fire resistant). They made it sound like you should be able to talk to their reps or them directly and they can point you to a specific UL detail. Did you actually talk to a manufacturer, or just look at their website? IME, Greenheck has been good (from factory direct, or through rep) in responding. I just never had a fire damper question to them.

JHA won't give you a detail, or design for you. but they can tell you what certificate you need, if other agencies than UL are acceptable etc.

Edit: I just saw Greenheck has a "life safety dampers" course coming up. They don't show the recent ones and it looks like you can't see old ones. I would touch base with them and see how to get signed up. They are free. Maybe there is a secret way to access past courses. Obviously other manufacturers also could offer education on their fire dampers.

 

[DrRTU]

I believe you have a simple membrane penetration of a rated assembly. This is common in multi-family high rise buildings. At most, you need a RD at the point of communication with the occupied space. You will find this with ceiling mounted exhaust fans which have a RD above the ceiling grille. See attached sketch i developed for you. UL lists plain metal thru a 1 hr assembly when used the correct firestop detail. Hilti & 3m are the easiest to use. Most reps will do a custom detail if needed. We place the details on our permit plans to help the AHJ.

 

[nuuvox000]

Like DrRTU said, you can use a radiation damper if you're only penetrating the membrane (one side of the horizontal fire-rated assembly). There is no approved fire damper at this time that you can use for a through penetration (all the way through the horizontal fire-rated assembly). Otherwise, you'll need a UL listing that matches what you're trying to do.

See 2018 IBC 714.5.1 which allows certain small pipes to penetrate a horizontal fire-rated assembly. If that doesn't answer your question then read section 714 over and over and over again until you understand (and hate) all of the penetration rules. If you draw a detail or picture showing specifics and more detail then we can take a look and see if what you're doing is feasible.