"Lacing" MC/AC through studs...

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celtic

celtic

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Would you consider MC/AC cables "laced" through the keyholes on metal studs (I'm talking vertically, not horizontially) a violation or not?

[330.30]
 
celtic said:
Would you consider MC/AC cables "laced" through the keyholes on metal studs (I'm talking vertically, not horizontially) a violation or not?
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You mean zig-zagged back and forth through the holes? Probably not prohibited, but it may not qualify as "secured."
 
celtic said:
Would you consider MC/AC cables "laced" through the keyholes on metal studs (I'm talking vertically, not horizontally) a violation or not?

[330.30]
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I would say that since the cable is run through the holes horizontally then it complies with 330.30(C)

The cable may be running vertical, but it is going through a horizontal hole.

I have used this method many times in the last 30 years without ever thinking that it would not be code compliant.
You still need to secure the cable within 12" of the box.
 
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Pierre C Belarge said:
If any cable is laced through the metal framing, vertically, a portion of the installation will be in the "web" of the stud.
How are you maintaining the 1-1/4 inch spacing from the front of the stud?
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The same way when it runs horizontally. It's in the same web, the cable doesn't take up any more space.
 
I install it this way from time to time, particularly when the walls are very tall. Saves fussing with clips or straps on top of a tall ladder.

When wiring the new Superior Walls (precast basement wall sections), I wire them this way. Weave the cable back and fourth through the precast holes when running parallel to the cast in "stud".
 
I would say that the chances of a cable getting hit by a screw when weaved inside the web, even if not secured are much greater. I have seen many times when more than one cable is installed in such a way. How is one to be sure that the cable is not to be pierced by a screw that is sure to be screwed through the web and into the space the cable occupies??? There is absolutely no way anyone here can tell me they are sure it would not happen.

CJs or any other type of standoff will relieve that situation.
 
Pierre C Belarge said:
CJs or any other type of standoff will relieve that situation.
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but there is no requirement to use a standoff to move the cable away from the stud. there are a bazillion pieces of Romex run through the center of studs. very few in proportion to their numbers ever get hit by a screw. MC that is running vertically inside a metal stud is even less likely to get punctured. the most likely scenario if a screw gets near it is that the MC will just move out of the way.
 
Vertical runs of MC

Vertical runs of MC

A local AHJ exception, is to run the MC on the face of metal stud if single
or use a Colorado Slim or other approved means to stand of a multiple run
of circuits. If inside one can be use a CS, etc. Its protects from the potential of the S/R screw.
I believe the AHJ's argument was that if weaved, that every time it
enters / exits a metal hole it has to be secured on both sides of the hole,
because its creates a parallelogram, thus requiring securing.
Go Figure : )
I know I personally don't like the stuff, I know its a time saver, I have reminded my co-workers more than once, that one needs to inspect all circuit once the armor is cut and before its inserted a device box.
 
If the cable is permitted to be run horizontally through the holes in the metal studs without being secured how is running vertically through the same holes any different?
 
infinity said:
If the cable is permitted to be run horizontally through the holes in the metal studs without being secured how is running vertically through the same holes any different?
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It is one of those issue in the code where art. 330.30(C) only allows horizontal runs not vertical runs. Can you get called on it-- I believe you can. Do I think you should get called on it-- No I don't.
 
Dennis Alwon said:
It is one of those issue in the code where art. 330.30(C) only allows horizontal runs not vertical runs. Can you get called on it-- I believe you can. Do I think you should get called on it-- No I don't.
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I think you are reading it wrong.

(A) General. Type MC cable shall be supported and secured
by staples, cable ties, straps, hangers, or similar fittings
or other approved means designed and installed so as
not to damage the cable.
(B) Securing. Unless otherwise provided, cables shall be secured
at intervals not exceeding 1.8 m (6 ft). Cables containing
four or fewer conductors sized no larger than 10 AWG
shall be secured within 300 mm (12 in.) of every box, cabinet,
fitting, or other cable termination.
(C) Supporting. Unless otherwise provided, cables shall
be supported at intervals not exceeding 1.8-m (6-ft)
Horizontal runs of Type MC cable installed in wooden
or metal framing members or similar supporting means
shall be considered supported and secured where such support
does not exceed 1.8-m (6-ft) intervals.
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No where does it say that you can't run them vertically. It says that if you run them horizontally through the studs that it is considered both secured and supported.

If you lace them through the studs vertically, they are for sure supported. You might need to secure them every 6 feet though, since there is some wiggle room on that. A few wire ties would handle it since wire ties are specifically mentioned as being an acceptable securing means.
 
I thought that the vertical weaving was being done in lieu of fastening. I am not sure I am following this. The code makes refers to horizontal runs sort of like an exception to the fastening rule. NO??? It does not give that except for the vert. run. I must be seeing something wrong.
 
Dennis Alwon said:
I thought that the vertical weaving was being done in lieu of fastening. I am not sure I am following this.
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You ARE following what my question is.
The others...I dunno...let's see how they weigh in on the "in lieu of fastening" comment.
 
petersonra said:
If you lace them through the studs vertically, they are for sure supported. You might need to secure them every 6 feet though, since there is some wiggle room on that. A few wire ties would handle it since wire ties are specifically mentioned as being an acceptable securing means.
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If they need additional securing every 6'....what's the point in lacing?
 
celtic said:
If they need additional securing every 6'....what's the point in lacing?
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May be no advantage at all. Personally, i would consider them effectively secured, and there can be no question they are supported when run this way.

But there could be some wiggle room for an inspector to say it is not secured.
 
petersonra said:
But there could be some wiggle room for an inspector to say it is not secured.
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Perhaps, but in the field, they're just not flagging this type of installation in my experience. Once the cable is terminated to where ever it's headed, it's pretty darned secure in the middle of the stud when laced like that.
 
So which is your(to all) "preferred" method:
- Laced and see ya later
- Cj'ed and see ya later
 
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