24 inch separation of receptacles in a rated wall

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mshields

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Boston, MA
Our specs call for this and I believe it to be a requirement. I just don't know where it is required? Can anybody point me in the right direction?

Also, If we're talking about stud walls, the contractor is telling me that if the two receptacles in question are on either side of a stud, then the 24 inch rule doesn't apply. Does he speak truth?

Thanks,

Mike
 
UL fire resistance directories for sure, here in FL the FBC addresses this. Check your local building code.

Yes he is correct, there may be ways around it, talk to AHJ- while on the subject madison straps for cut-ins can't be used either.
 
Some day, I'll own a copy of the UL Orange Book (books actually. 2 volumes). As an electrician, I keep bumping into these requirements. I see now that Allied has listed boxes that don't require the 24" seperation. Might want to check out their site if you can buy Allied in your area.
 
From Volume One of 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.

Metallic boxes located on opposite sides of walls or partitions shall be seperated by a minimum horizontal distance of 24in. This minimum seperation distance between metallic boxes may be reduced when "Wall Opening Protective Materials" (CLIV) are installed according to the requirements of their Classification.

Metallic boxes shall not be installed on opposite side of walls or partitions of staggered stud construction unless "Wall Opening Protective Materials" are installed according to the requirements of their Classification.

Roger
 
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He must be a hundred and five

He must be a hundred and five

Google? I'll have to sharpen my Google skills. I don't see how one could find paragragh out of a UL document pertaining to outlets in rated walls! But I'll keep it in mind - thanks
 
Is there a U.L. article that address' the Non-Metallic Boxes? Most NM boxes are listed as a 2hr box. I see the previous post pertaining to Metallic boxes.

Tom:smile:
 
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