tiger grip in a fire rated wall?

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ibew441dc

ibew441dc

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To my knowledge the NEC does not specifically address cut-in boxes installed in fire rated walls.

My question is.... Is it permitted to fish down a fire rated wall and install a cut-in type device box?

If it is permitted are there restrictions ie. size , separation, height, fire pads, ect.?
Where would one look to find this info?

I have had mixed results in opinions from peers, and a few who claim to know the answers can't give me a reference .

Thanks in advance,
 
Nick is correct.

It's either in the Gypsum manuel or the UL Fire Resistive Manuel. It may be in the building code too.

Like Nick I can't remember, but I know what it says.
 
From the UL Fire Resistance Directory.

WALL AND PARTITION ASSEMBLIES

Metallic Eletrical Outlet Boxes

Listed single and double gang metallic outlet and switch boxes with metallic or nonmetalliccover plates may be used in bearing and nonbearing wood stud and steel stud walls with ratings not exceeding 2h. These walls shall have gypsum wallboard facings similar to those shown in Design Nos. U301,U411, and U425. The metallic outlet or switch boxes shall be securely fastened to the studs and the opening in the wallboard facing shall be cut so that the clearance between the box and the wallboard does not exceed 1/8 in. The surface area of individual metallic outlet or switch boxes shall not exceed 16 sq in. The aggregate surface area of the boxes shall not exceed 100 sq in per 100 sq ft of wall surface.



Roger
 
Nick said:
I don't have a reference handy but if memory serves in order to maintain the rating of the wall boxes must be securely fastened to the studs. Cut in boxes obviously do not meet this requirement.
Click to expand...
Presumably an old-work box with internal screws mounted to the stud would be adequate? Something like the Arlington One-Box.

Cheers, Wayne
 
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