Structural steel roof floor beam penetrating 1hr duct shaft.

[Fast_Edd1e]

Michigan Building Code 2015
I have a duct shaft that is 1 hour rated going between 2 floors. There is a structural floor beam that runs thru this shaft. Floor beam is not rated or required to be.

Do I treat this as a thru wall penetration and utilize a Hilti type fire caulk? Does the beam need to be rated?

I feel like this is a similar condition to a strip mall where the beam can pass thru the 1hr wall and just fire caulked.

Link to image sketch.

https://imgur.com/a/NFqZQmG

 

[BN4537]

Not sure what the 2015 Michigan Building code says, 2018 IBC says that structural elements can penetrate a shaft enclosure if protected per 714 for fire barriers.
714.4.1 exception says that if the penetrating item is steel, ferrous, etc., it needs to be protected with in one of two ways, the second being to fill the annular space with something that meets ASTM E119 or UL 263 for, in your case, 1 hour.

So if you use the right fire caulk, I think that would be fine.

 

[Fast_Edd1e]

Not sure what the 2015 Michigan Building code says, 2018 IBC says that structural elements can penetrate a shaft enclosure if protected per 714 for fire barriers.
714.4.1 exception says that if the penetrating item is steel, ferrous, etc., it needs to be protected with in one of two ways, the second being to fill the annular space with something that meets ASTM E119 or UL 263 for, in your case, 1 hour.

So if you use the right fire caulk, I think that would be fine.

Michigan building code is just an extension of IBC.
Those are the two code sections I’ve been looking at for my response to the contractor. Thank you for the input.

 

[ADAguy]

unprotected steel will transfer heat to adjacent surfaces it is in contact with, Hilti won't prevent that (will it?)

 

[Paul Sweet]

Is a rated shaft required? IBC 717.6.3 allows ducts penetrating floors that are not required to be rated and connecting 2 or 3 stories to not be enclosed in shafts.

 

[e hilton]

unprotected steel will transfer heat to adjacent surfaces it is in contact with, Hilti won't prevent that (will it?)

If the shaft is 1 hr rated, doesnt that mean that after 1 hr you can expect the fire to break through and spread to other parts of the building? So my point is ... would the beam transfer enough heat in less than 1 hr to cause something outside the shaft to ignite?