MC on back side of steel stud framing.

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RES

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Does the NEC proscribe fastening MC cable to the back side of steel stud framing? I know that inspectors, generally, want the the MC fastened to the face of the stud.
 
RES said:
Does the NEC proscribe fastening MC cable to the back side of steel stud framing? I know that inspectors, generally, want the the MC fastened to the face of the stud.
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The words "where supporting is impractical", really leave it up to interpretation. If its a framed wall close to a concrete wall, and you're running the MC in between the two, some people would consider that a "chase" or consider the wire fished in, and not make you strap it. But I suppose the right inspector could buck against it. Although I run wire in cuch areas every chance I get, just for that reason, not having to strap it (also not having to drill or punch studs)
 
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mc on back side of steel stud framing

mc on back side of steel stud framing

I thought running parallel with the stud on the back side was to be avoided, if possible. Apparently, it is not a code issue. Thank you.
 
When running parallel to a framing member you must keep the cable back 1.25".


300.4(D) Cables and Raceways Parallel to Framing Members
and Furring Strips. In both exposed and concealed
locations, where a cable- or raceway-type wiring method is
installed parallel to framing members, such as joists,
rafters, or studs, or is installed parallel to furring strips, the
cable or raceway shall be installed and supported so that the
nearest outside surface of the cable or raceway is not less
than 32 mm (11⁄4 in.) from the nearest edge of the framing
member or furring strips where nails or screws are likely to
penetrate. Where this distance cannot be maintained, the
cable or raceway shall be protected from penetration by
nails or screws by a steel plate, sleeve, or equivalent at least
1.6 mm (1⁄16 in.) thick.


Exception No. 1: Steel plates, sleeves, or the equivalent
shall not be required to protect rigid metal conduit, intermediate
metal conduit, rigid nonmetallic conduit, or electrical
metallic tubing.


Exception No. 2: For concealed work in finished buildings,
or finished panels for prefabricated buildings where such
supporting is impracticable, it shall be permissible to fish
the cables between access points.


Exception No. 3: A listed and marked steel plate less than
1.6 mm (1⁄16 in.) thick that provides equal or better protection
against nail or screw penetration shall be permitted.
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I've done it with both wood and steel studs when the studs were against an old exterior wall. I wouldn't do it if there was a room behind the wall, especially if it might be finished later.
 
what is on back side - if a concrete wall and there will be no access to the cable then what is there to protect it from besides ignorant inspectors.
 
Personally I think you have all misunderstood the question.:grin:

IMO he is asking about letting the MC be 'inside' the open side of a metal stud instead of being on the face or flush side of the metal stud.
 
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iwire said:
Personally I think you have all misunderstood the question.:grin:

IMO he is asking about letting the NEC be 'inside' the open side of a metal stud instead of being on the face or flush side of the metal stud.
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It was bit hard to understand but if as your thinking then the 1 1/4 rule applies

And i hope nec is typo for mc
 
iwire said:
Personally I think you have all misunderstood the question.:grin:

IMO he is asking about letting the MC be 'inside' the open side of a metal stud instead of being on the face or flush side of the metal stud.
Click to expand...

ack I think you are right
 
iwire said:
Personally I think you have all misunderstood the question.:grin:

IMO he is asking about letting the MC be 'inside' the open side of a metal stud instead of being on the face or flush side of the metal stud.
Click to expand...

That was first thing that crossed my mind and I thought to myself why not I have done it many times. But then reading the following replies got my mind on running it behind the studs where there is another barrier very close to the metal stud wall. I see this a lot with wood studs but seldom if ever with steel studs - they usually need drywall on both sides or the wall is not very strong otherwise.
 
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