NM run throughPVC

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ShockedOneinAZsun

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Yuma, Arizona
Residential: The code says that you must protect NM cable when running through floors. I ran a short length of NM through a 3/4" PVC conduit, extended at least 6" out of the floor and wall, yet the inspector says I cannot run NM through conduit in any circumstance. Am I wrong in my assumption that the code says I can run NM in a PVC conduit for a short run from a wall to a kitchen island? 334.15 c
 
NM cable is not permitted in underground raceways per 300.5(B). The PVC sleeve between floors should be approved per the 334.15 as referenced by you.
 
Maybe the inspector commented about the PVC because it was schedule 40?

2005 NEC 334.15(B) calls out a bunch of different raceways:
334.15 Exposed Work
(B) Protection from Physical Damage Cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC rigid nonmetallic conduit, or other approved means. Where passing through a floor, the cable shall be enclosed in rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC rigid nonmetallic conduit, or other approved means extending at least 150 mm (6 in.) above the floor.
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Thanks for your reply. I showed him this exact passage, and confirmed that it was Schedule 80. He was what we call a "Triple Threat" in that he inspects three trades, yet doesn't know any of them really well. Everything I challenged him on, he had to go back to the office and get an "official" opinion on, and I had to call him for the ruling.
 
Pls clarify for me. I have a job that will require 5 NM #12 in a 2" PVC run above the floor on a garage wall as a sleeve to the panel. Its about a 12 ft run... Is this permitted?
 
Oakey said:
Pls clarify for me. I have a job that will require 5 NM #12 in a 2" PVC run above the floor on a garage wall as a sleeve to the panel. Its about a 12 ft run... Is this permitted?
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Yes, but these conductors will require derating.
 
bphgravity said:
NM cable is not permitted in underground raceways per 300.5(B). The PVC sleeve between floors should be approved per the 334.15 as referenced by you.
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The way I see it article 314.15(B) allows it to be schedule 40. It says listed surface nonmetallic raceway, or other means. As long as it's not burried I would use schedule 40, it's identified for use above ground. This section says "protection from physical damage".
 
pismo said:
The way I see it article 314.15(B) allows it to be schedule 40. It says listed surface nonmetallic raceway, or other means. As long as it's not burried I would use schedule 40, it's identified for use above ground. This section says "protection from physical damage".
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I think that you meant 334.15(B). And where does it say "listed surface nonmetallic raceway"?
 
Similar question, protecting cable

Similar question, protecting cable

I have a somewhat similar question I have NM cable that runs under roofing material (a flat roof) and is covered by a metal C channel to protect it.

Does this need to be inside EMT Rigid or PVC?

it goes ...... Roof 2x6's, NM cable, Metal C channel covering the NM and stapled to the roofing 2x6's and then all is covered by asphalt roll roofing.

Thanks for the help
 
dgpach said:
I have a somewhat similar question I have NM cable that runs under roofing material (a flat roof) and is covered by a metal C channel to protect it.

Does this need to be inside EMT Rigid or PVC?

it goes ...... Roof 2x6's, NM cable, Metal C channel covering the NM and stapled to the roofing 2x6's and then all is covered by asphalt roll roofing.

Thanks for the help
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What I have done in the past is pull the NM to a four-square in a closet (somewhere not visibly obnoxious). EMT with THHN/THWN from the junction box to light in the ceiling, between the roof material and the ceiling above. Single-gang P-ring on j-box, blanked at trim.

I wouldn't think under the roofing material would be considered a damp location, but I could understand an inspector having trepidation about approving it. I would consider contacting the AHJ if you want to run NM in the area you're considering.
 
infinity said:
I think that you meant 334.15(B). And where does it say "listed surface nonmetallic raceway"?
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You're right, I meant 334.15(B). The last sentance says "listed surface metal or nonmetallic raceway".
 
pismo said:
You're right, I meant 334.15(B). The last sentance says "listed surface metal or nonmetallic raceway".
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What year NEC are you looking at.

The 2005 NEC 334.15(B) requires schedule 80 used if you chose RNC.

BTW it also says 'or other approved means' so if the AHJ approves a bamboo stock for protection that would also be compliant. :D
 
pismo said:
You're right, I meant 334.15(B). The last sentence says "listed surface metal or nonmetallic raceway".
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I suspect that Pismo is reading the 2002 NEC.

Pismo, Article 386 = surface metal raceway and Article 388 = surface nonmetallic raceway. . .

As opposed to Article 352 for rigid nonmetallic conduit.
pismo said:
The way I see it article 314.15(B) allows it to be schedule 40.
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Consider:
2002 NEC 388.100 Construction.

Surface nonmetallic raceways shall be of such construction as will distinguish them from other raceways.
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Rigid nonmetallic conduit is not labeled as "surface nonmetallic raceway", and, therefore is not governed by 388.
 
Al are you telling me that NM can't be used in PVC because it will get wet or be subect to excessive moisture or dampness. I am just trying too understand 334 better.
 
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