Recessed boxes Fire rated wall

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hhsting

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Glen bunie, md, us
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Can recessed boxes in fire rated walls must meet one of the following installation: A. Separated by horizontal distance of no less then 24 inch. B. Be surrounded by a fire rated gypsm in 5 sides. C. Back of boxes wrapped in fire resistant putty similar to spec seal seal fire rared puddy pads?

If yes then I cannot find this in NEC 2017. Is it in some other codes?
 
Yes to all 3.
You will probably have to look in the IRC, IBC, Gypsum Manual, Hilti Manual and/or 3M Manual.
IMO this should be a building inspectors concern.
 
rc/retired said:
Yes to all 3.
You will probably have to look in the IRC, IBC, Gypsum Manual, Hilti Manual and/or 3M Manual.
IMO this should be a building inspectors concern.
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Agree building/fire code. But we've had to place it in relation to box installation. Also recently seen an internal barrier product that goes inside a box as a fire retardant membrane, it supposedly if heat of a fire gets to it, begins breaking down into a fire retardent expanding foam. It is particularly useful if fire is initiated internally from electrical fault making the enclosure self extinguishing. Atleast that is how it was marketed, no first hand experience with product.
 
Fred B said:
Agree building/fire code. But we've had to place it in relation to box installation. Also recently seen an internal barrier product that goes inside a box as a fire retardant membrane, it supposedly if heat of a fire gets to it, begins breaking down into a fire retardent expanding foam. It is particularly useful if fire is initiated internally from electrical fault making the enclosure self extinguishing. Atleast that is how it was marketed, no first hand experience with product.
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Thank you. But we all know that AFCI breakers prevent electrical fires.

Ron
 
Fred B said:
Agree building/fire code. But we've had to place it in relation to box installation. Also recently seen an internal barrier product that goes inside a box as a fire retardant membrane, it supposedly if heat of a fire gets to it, begins breaking down into a fire retardent expanding foam. It is particularly useful if fire is initiated internally from electrical fault making the enclosure self extinguishing. Atleast that is how it was marketed, no first hand experience with product.
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We installed thousands of them on our last apartment complex project. 100X better than the putty pads on the outside. The internal pad is the size of the inside of the box just peel and stick. That's it. (y)
 
infinity said:
We installed thousands of them on our last apartment complex project. 100X better than the putty pads on the outside. The internal pad is the size of the inside of the box just peel and stick. That's it. (y)
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Were the boxes metallic or non-metallic (I have not found an insert that was rated for non-metallic. If yours is, please provide manufacturer's name)
 
infinity said:
We installed thousands of them on our last apartment complex project. 100X better than the putty pads on the outside. The internal pad is the size of the inside of the box just peel and stick. That's it. (y)
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is this a hilti or 3m product? i have only used the external pads, but these sound much better. make and model please?
 
Hilti, the ones we used even has a slit for the ground screw.

9533063004190.jpg


Firestop box insert - Firestop putties - Hilti USA

Hilti Firestop putties - Firestop box insert - Intumescent box insert designed to help protect electrical outlet boxes from fire and smoke
www.hilti.com www.hilti.com
 
infinity said:
Hilti, the ones we used even has a slit for the ground screw.



Firestop box insert - Firestop putties - Hilti USA

Hilti Firestop putties - Firestop box insert - Intumescent box insert designed to help protect electrical outlet boxes from fire and smoke
www.hilti.com www.hilti.com
Click to expand...

what is the reference to NEC 314.16 on the package? that makes no sense to me. how does that come into play? does the addition of the pad reduce the box allowable fill?
 
macmikeman said:
300.21 informal note in the NEC.

Sorry Ciro, I put the first sentence in the box this morning and forgot to hit post I guess.
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thanks. i had always felt that 300.21 was woefully inadequate in its direction and did not realize it was shifting the heavy lifting to the IBC and IRC
we are still on 2006 IBC here
 
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