Does smoke partition require fire and smoke damper at penetration?

project development & documentation
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It’s known that fire and smoke dampers are located inside the HVAC ductwork to prevent the spread of smoke and gases.

So, are HVAC ducts penetrating rated partitions required to have fire and smoke dampers ?

Since smoke partition is not fire rated, then does it NOT require damper at penetration ?

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HI @JessicaY that’s a great question! Let’s see if one of our expert architects can help with this one. @coachbryanhadley could you help Jessica with these questions?

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Can you please provide some answers as I will be taking my PDD exam this Saturday ? Thank you

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@coachdarionziegler are you able to help answer this question?

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Hi @JessicaY,

Fire dampers also act as smoke dampers! There will only one damper (and not a fire damper and then smoke damper). Both fire dampers and smoke dampers are designed to close upon detection of heat/fire. However, fire dampers carry a rating while smoke dampers do not.

Dampers are required at smoke partitions as well, even if they are not rated! See snippets of the IBC 2018 below:

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Here are some examples of fire dampers: https://www.ruskin.com/category/242~Fire-Dampers
And here are some examples of smoke dampers:https://www.ruskin.com/category/522~Smoke-Dampers

It’s important to note while smoke partitions do not require a rating, smoke barriers do! So at smoke barriers you are actually going to use fire dampers at your penetrations, and not smoke dampers.

This resource is a little off topic, but I think it provides some good context for fire walls vs. smoke partitions vs. smoke barriers:

Hope this helps!
-Darion

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Thank you so much for insightful explanation. That clears up a lot of confusion for me. Based on what you explained, I do want to point out that the answer provided in the PDD practice exam Form 1 question 66 is not exactly correct (see attached). The correct answer should exclude smoke damper as HVAC ducts penetrating RATED partitions are required to use fire damper only. This question really had me confused…

To summarize the points you made, please confirm the following:

-Fire damper (RATED) only applies to penetration at Rated walls/partitions (fire walls, fire barriers, fire partitions, and smoke barriers).

-Smoke damper (NON-RATED) should only apply to smoke partitions as they’re also not fire rated.

However, the information from IBC has some discrepancies from your explanation about smoke barrier, and fire / smoke dampers. IBC 717.4 and 717.5 mentioned that there is a combination fire/smoke damper, or providing both a fire damper and a smoke damper. IBC 717.5.5 also states that smoke dampers shall be provided at penetrations of smoke barriers (this is where you said it should use fire dampers instead). Please help clarify this.

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Hi @JessicaY,

I’m afraid I had to delete your photo as we do not allow posting of paid Black Spectacles Content or any other 3rd party paid content! Thanks for brining that up though - I get what the question is going for but the wording is a little suspect.

If you have a wall that is acting as both a smoke barrier and a rated partition/barrier then you will have a combination fire/smoke damper. This is one system, and not a separate smoke damper and then fire damper. Sorry I didn’t answer that well!

If the wall is rated and the penetrations are required to be rated, a combination fire/smoke damper should be used unless not required per other sections of the code. There are some instances for example where 1 hour rated assemblies are not required to have fire dampers – for example 717.5.2 exception 3. I think what section 717.5.5 is that smoke barriers must have smoke dampers no matter the rating. It’s not negating that a rated assembly may cause a combination smoke/fire damper combo to be needed, but is insuring that at least a smoke barrier will be present.

I found this lunch and learn that does a good job showing the different types of dampers and when each should be used:

And here’s a resource from the ICC I found describing requirements for firestopping penetrations which does a great job explaining some this better:

I also found this resource helpful:

Hope this helps!
-Darion

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Thank you for the helpful clarification.

Jessica

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I apologize that I was not able to respond sooner. Looks like Darion was able to help, with a rich back and forth that followed.