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Can someone point me towards the codes/requirements for a 1 hr fire rated assembly?

I was told MC only...true?

Job is in PA.
Not in Ontario nm wire is fine but it has to terminate to a metal box.
 

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As I recall.... same (nm and metal boxes) in Cali last code cycle. (based on IBC) (at least we did not have any permit exception)

(Can't even remember if that was building code/NEC/or fire code)
 

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Only if things are different in PA, otherwise no, that's not generally true, you can use NM in fire-rated assemblies in residential work. You'll need to be careful about penetrations, and seal them (which may result in de-rating your conductors). You also have to check on the rating and possibly spacing or proximity of NM boxes.

It could be that your source is confused about different types of construction (Types 1-5) or is aware of restrictions in some types of occupancies (places of assembly, e.g.).

Or PA is different.
 

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Discussion Starter · #5 ·
Only if things are different in PA, otherwise no, that's not generally true, you can use NM in fire-rated assemblies in residential work. You'll need to be careful about penetrations, and seal them (which may result in de-rating your conductors). You also have to check on the rating and possibly spacing or proximity of NM boxes.

It could be that your source is confused about different types of construction (Types 1-5) or is aware of restrictions in some types of occupancies (places of assembly, e.g.).

Or PA is different.
Agreed to all. I will talk to the inspector if he ever calls me back.
 

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Discussion Starter · #8 ·
It has to be a rated box. No holes, normally drawn so there are no corner seams.

Tom
Since I posted I started looking up some materials, looks like nonmettallic boxes are rated...I will just run everything by the inspector before we get in a bind.

It's only one wall in the building.
 

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Metal boxes or rated plastic boxes are OK. Look for the 2HR symbol stamped inside the plastic boxes, metal box needs no markings.

Maximum size hole (not box) is 16 square inches. 5S box with 2 gang ring OK. No more than 100 sq inches of opening in any 100 square foot area.
Minimum separation between boxes is 24 inches unless you use listed fire pads or other products that allow closer spacings.

3 gang boxes and panelboards, etc. will require different solutions such as boxing in subject to local approvals.
 
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