Knob and Tube - home inspection

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kwired said:
FMC is not limited to 6 feet.

It is limited to 6 feet when allowed and used as the EGC, but if you pull a green there is no length limitation.

There is no unsupported whip rules that can apply either when over six feet, so if your whip is more than six feet you need to follow the general support rules.
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Not sure if you know this but he's from Chicago, they still wire full houses in EMT and have crazy restrictions on different wiring methods in certain areas. I don't know all the details but I know they don't like Romex or flexible wiring methods very much.

Tips for EMT in dwelling unit

Hi all. Long time, no post; hope all of you are well. Normally, I don't get involved with too much residential work, but a buddy of mine -- who does mostly residential -- stepped aside and recommended me for this job because the contractor has mandated it be done in EMT due to local ordinance...
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SSDriver said:
Not sure if you know this but he's from Chicago, they still wire full houses in EMT and have crazy restrictions on different wiring methods in certain areas. I don't know all the details but I know they don't like Romex or flexible wiring methods very much.

Tips for EMT in dwelling unit

Hi all. Long time, no post; hope all of you are well. Normally, I don't get involved with too much residential work, but a buddy of mine -- who does mostly residential -- stepped aside and recommended me for this job because the contractor has mandated it be done in EMT due to local ordinance...
forums.mikeholt.com

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emt and nail plates??? 😵 ~RJ~
 
SSDriver said:
Not sure if you know this but he's from Chicago, they still wire full houses in EMT and have crazy restrictions on different wiring methods in certain areas. I don't know all the details but I know they don't like Romex or flexible wiring methods very much.
Click to expand...
The point I was trying to make w/ @kwired is that my original comment NEVER claimed that ALL FMC was limited to 6 ft. It was a very short, general statement, that wasn't even the focus of my comment, that there are length limitations w/ FMC that can make things tricky... and there are length limitations in the NEC, as he himself points out.

The argument about ALL FMC being limited to 6 ft. was a different, subsequent comment referring to local amendments that I have to contend with.

Ultimately all of this was digression from the OP. I was merely trying to comment on the OP's hesitancy to replace K+T wiring by saying we love those kind of jobs around here and one way to do it, is via FMC, but... blah blah blah, there are some length restrictions that can make it tricky...

...and enter lengthy digression from the OP topic, lol.
 
hbiss said:
You don't know what MC is? What are you, some kind of residential only guy? :eek:

He posted pictures of it going to those boxes. See Art. 330.

-Hal
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I know what MC is, just wondered what the "C" stands for, I was thinking Cable but Larry reminded me Clad

so its Metal Clad Cable

(was in reference to the theory that MC is a type of conduit mentioned in earlier posts)
 
Generally speaking, MC and even EMT are considered no more "armored" than NM cable. Thus the nail plates over EMT.
 
LarryFine said:
Generally speaking, MC and even EMT are considered no more "armored" than NM cable. Thus the nail plates over EMT.
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What do they have for us on Metal studs? I've seen metal studs that definitely would not have the 1.25 inch setback for the cable run holes.
 
Fred B said:
What do they have for us on Metal studs? I've seen metal studs that definitely would not have the 1.25 inch setback for the cable run holes.
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With metal studs you run the cables through the punched openings which are large enough to allow the cable to move out of the way of a nail or screw.

-Hal
 
Fred B said:
What do they have for us on Metal studs? I've seen metal studs that definitely would not have the 1.25 inch setback for the cable run holes.
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With metal studs and MC cable no protection is required when running through holes in the studs even if the stud holes are less than 1.25" from the edge. 1 5/8" studs are used all of the time with MC cable through the holes in the studs and no protection.

I would also add that nail plates are not required for EMT through studs.
 
LarryFine said:
Generally speaking, MC and even EMT are considered no more "armored" than NM cable. Thus the nail plates over EMT.
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Eh, I don't know about that one. I think your conclusion here ignores the reality of a grey area between two absolutes. It's a scale.
It's definitely possible to drive a screw into EMT, or a nail from a nail gun, but THE SAME AS NM!? No way.
 
infinity said:
I would also add that nail plates are not required for EMT through studs.
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You sure? I thought they were if it's a certain distance from the edge?
It's definitely required if you notch. That I'm near certain of.

I do nail plates on my EMT anyway. It's cheap and prevents you from having to open a wall up again and fix something the drywallers messed up.
But I feel like there is a code requirement here.
 
hbiss said:
With metal studs you run the cables through the punched openings which are large enough to allow the cable to move out of the way of a nail or screw.

-Hal
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You can't prove that by me, lol.
I have a guy that does some framing and sheet rock for me, he can hit it, not only hit it but drive right into it. He hit free floating mc in a wall space that lower studs didn't aline with upper studs, mc floating across a 16" space, hit it dead center of space and of the mc, right into a spiral groove driving screw in and blowing the breaker. I too always thought the cables would just move. That became a 2 junction box repair.
 
infinity said:
I would also add that nail plates are not required for EMT through studs.
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If it's not an NEC requirement, then it's either another building code issue like IRC or a local amendment. I know I got it from somewhere and didn't just invent it. I was introduced to nail plates long before I ever installed my first NM. So I know I'm not conflating NM requirements with EMT.
 
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