NM cable in conduit

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3rdworldelectric

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a contractor told me it was against code to put NM cable(romex) in conduit for protection from physical damage in a furred out wall....i tried looking it up all i found was that it can be put in conduit for protection in exposed situations...is it ok or not. please include code section. thx
 
There is no article that specifically says that you can protect NM with conduit. At the same time there is no article that says you cannot. If you are sleeving it to protect the wire from damage then go at it. You must make sure the cable doesn't overfill the conduit.
 
3rdworldelectric said:
please include code section. thx
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Choose your conduit and check the section listed.

IMC - 342.22

RMC - 344.22

FMC - 348.22

LFMC - 350.22

RNC - 352.22

HDPE - 353.22

EMT - 358.22

There are more, pretty much ".22" of each raceway article.

Then finish up with NM - 334.15(B)
 
What type of contractor told you this?

Roger
 
At the risk of exposing my ignorance, how thick is EMT?

I wouldn't immediately leap to the conclusion it was 1/16th" thick, in the application of 300.4(D).

Since the wiring method is NM and the sleeve likely isn't continuous from box to box, then the EMT would have to be at least a 16th of an inch thick to qualify as a nailplating sleeve.

It may sound like a ridiculous question, but I have my fair share of those every now and then. :D
 
I have installed plenty of times in pvc for protection purposes. I've never had an issue with inspection. Take that for what it's worth. :grin: The only prohibition would be outdoors or undergound because it still remains wet location when you do.
 
I just ran into this situation last week on a rough with 2 walls containing sliding pocket doors. Each had a sconce light right on the outside of the pocket wall. My boss laughed when I said lets sleeve the NM with EMT. Just to show me, he grabbed a piece of EMT and a drywall screw and began to screw through/poke holes in the EMT without even holding/starting the screw strait. He also drilled some off center, on the edge of the conduit (where I thought the screw for sure would slip off. The screw easily caught/penetrated right through the edge of the EMT.

EMT wont provide protection in this situation. Those screws are SHARP!
 
fzzzt said:
EMT wont provide protection in this situation. Those screws are SHARP!
Click to expand...

You're drywall screws must be on steroids. I tried to do this once, and failed even when I set up the drill/driver in my drill press and held the EMT in a vise!
 
(A) Cables and Raceways Through Wood Members.
(1) Bored Holes. In both exposed and concealed locations,
where a cable- or raceway-type wiring method is installed
through bored holes in joists, rafters, or wood members,
holes shall be bored so that the edge of the hole is not less
than 32 mm (11⁄4 in.) from the nearest edge of the wood
member. Where this distance cannot be maintained, the
cable or raceway shall be protected from penetration by
screws or nails by a steel plate or bushing, at least 1.6 mm
(1⁄16 in.) thick, and of appropriate length and width installed
to cover the area of the wiring.
Exception No. 1: Steel plates shall not be required to
protect rigid metal conduit, intermediate metal conduit,
rigid nonmetallic conduit, or electrical metallic tubing.

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

ok...

334.17 Through or Parallel to Framing Members.
Types NM, NMC, or NMS cable shall be protected in
accordance with 300.4 where installed through or parallel
to framing members. Grommets used as required in
300.4(B)(1) shall remain in place and be listed for the
purpose of cable protection.

(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.
 
480sparky said:
You're drywall screws must be on steroids. I tried to do this once, and failed even when I set up the drill/driver in my drill press and held the EMT in a vise!
Click to expand...

On commercial jobs often the drywallers use drill tip screws....they can go through EMT no problem.
 
georgestolz said:
I wouldn't immediately leap to the conclusion it was 1/16th" thick, in the application of 300.4(D).
Click to expand...

I could run PVC and not have to nail plate it.

IMO the code is a bit odd with its ideas of physical protection.
 
roger said:
What type of contractor told you this?

Roger
Click to expand...
he's a GC and he said there there would be a heat issue because of the NM sheathing....it seemed wrong....just for a 14/2 in a 1/2" emt. thanks for taking the time with this..this is a great site
 
We had a job where we installed EMT in a wall and came back after drywall to install the conductors. We couldnt get the fish tape through there were
about 5 drywall screws in a vertical run of about 12 ft.
EMT not a good idea!
 
oh yea self tappers in a drywallers hands are dangerous think and metal studs encourage them; same as cabinet installers with self tappers and metal studs..I am not the only one who has experienced it, that makes me feel better..
 
tom25 said:
We had a job where we installed EMT in a wall and came back after drywall to install the conductors. We couldnt get the fish tape through there were
about 5 drywall screws in a vertical run of about 12 ft.
EMT not a good idea!
Click to expand...


How in the world were they that consistently off-line with the stud? Did they look at the pipe as an extra spot of support? Wouldn't surprise me. :roll: Or were you that close??
 
480sparky said:
You're drywall screws must be on steroids. I tried to do this once, and failed even when I set up the drill/driver in my drill press and held the EMT in a vise!
Click to expand...


That makes me wonder, how long ago did you try this with the vise? The quality and thickness of the EMT or the screws must have changed over time? I just walked out to my truck and tried it again. Using standard 1/2 EMT and standard black drywall screws without the drill type tip... Once again, they "caught" the surface of the EMT pretty easily and went right thru. Tried off center with same result.
 
TwinCitySparky said:
That makes me wonder, how long ago did you try this with the vise? The quality and thickness of the EMT or the screws must have changed over time? I just walked out to my truck and tried it again. Using standard 1/2 EMT and standard black drywall screws without the drill type tip... Once again, they "caught" the surface of the EMT pretty easily and went right thru. Tried off center with same result.
Click to expand...

This was about 10 years ago.
 
480sparky said:
You're drywall screws must be on steroids. I tried to do this once, and failed even when I set up the drill/driver in my drill press and held the EMT in a vise!
Click to expand...
But then this is his boss; maybe he's on steroids:
bio-hulk.jpg
 
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