Panelboard in 2 hour rated wall

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cppoly

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Is there a code section that refers to this? I can't find a section in article 408 that allows or doesn't allow this.

Thanks
 
This issue is addressed in the building code not the electrical code.

IBC Section 714.3.2 addresses membrane penetrations which a cabinet (The enclosure that the panelboard is installed in) would be.

Exception #1 to 714.3.2 does allow small steel electrical boxes that do not exceed 16 square inches but it would not apply to a cabinet for a panelboard.

Chris
 
Joe Villani said:
3m has an endothermic mat for this type of installation.

http://solutions.3m.com/wps/portal/...hermic-Mat-E-5A-4?N=5433099+3294069023&rt=rud


http://www.google.com/url?url=http:...ic+mat&usg=AFQjCNHOYcA186aZ0G3Qh5OZJvVlFWEyGw

Just make sure you get an engineering judgement or have a listed penetration detail available for the inspector.
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One may be able to use products like those you mentioned or modify the wall in some way to preserve the finish rating, but you can't just cut into the finish rating with that large of a penetration. Any method used may be good idea to pre approve with the inspector as well or you may be doing it over and repairing what you damaged on the original finish.
 
Thanks for the input. The panel is going to be put in a new corridor wall. The takeaway is that it can be done, just with the proper materials to maintain the rating?
 
cppoly said:
Thanks for the input. The panel is going to be put in a new corridor wall. The takeaway is that it can be done, just with the proper materials to maintain the rating?
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Problem is there is no proper way to do it that is "approved" People try to do it all the time and as was kind of mentioned, it's gets messed up and then you've really created an issue.

Remember that a two hour wall is two layers of drywall, a two by four, and two layers of drywall. The vertical seams of the drywall are not allowed to over lap either. So how would you build an approved wall cavity with those issues in mind?
 
cowboyjwc said:
Problem is there is no proper way to do it that is "approved" People try to do it all the time and as was kind of mentioned, it's gets messed up and then you've really created an issue.

Remember that a two hour wall is two layers of drywall, a two by four, and two layers of drywall. The vertical seams of the drywall are not allowed to over lap either. So how would you build an approved wall cavity with those issues in mind?
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How do you not overlap vertical seems in a corner?:D

Does the two by four need to be in there or is the net four layers of drywall the most critical thing?

I have seen instances where they allowed four straight layers with nothing else in between to plug an old window or other existing opening where they wanted a two hour rating.
 
Maintain the two hours behind the panel into a recess, then surface mount the panel. Protect all penetrations through the two hour assembly (home runs).
 
kwired said:
How do you not overlap vertical seems in a corner?:D

Does the two by four need to be in there or is the net four layers of drywall the most critical thing?

I have seen instances where they allowed four straight layers with nothing else in between to plug an old window or other existing opening where they wanted a two hour rating.
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That's my point about no approved method. In most two hour assemblies you have to flag the drywall through.
 
~ ~ @ ~ ~
"Does the two by four need to be in there or is the net four layers of drywall the most critical thing?"
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Yes, ...the 2 x 4's are part of the fire tested assembly; as well as, the 4 layers of
gyp. board........All of the components are necessary and "required" to have an
approved type of fire rated assembly.

Remove any one component or alter the overall wall or ceiling assembly, and
the whole thing is no longer approved. :happysad:


~ ~ @ ~ ~
 
cppoly said:
Thanks for the input. The panel is going to be put in a new corridor wall. The takeaway is that it can be done, just with the proper materials to maintain the rating?
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In the opening post you mentioned a 2 hour wall. With a 2 hour rating, I suspect that it is not a corridor, but what the IBC calls an exit passageway. I don't see a circumstance in the IBC where a 2 hour wall is required if it is only a corridor. An exit passageway looks like a corridor but is treated more strictly under IBC rules. If what you have is actually an exit passageway, A panel is not on the list of items that the IBC allows to penetrate an exit passageway wall regardless of how well you protect it. See IBC Section 1023.6. You need to check with the building department before penetrating the wall.
 
scrypps said:
Im not sure if by "no approved method" that includes 5-siding the panel within the stud bay?
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If you look in the Gypsum manual or any of the fire protection product manuals, you will not find anything that would allow you to install a panel in any rated wall, let alone a two hour one. "Approved" means just that. "Allowed" is another thing.
 
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