NM cable in PVC , in a slab, is it that complicated?

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Snowbound

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Local lead inspector has deemed all cables passing through concrete , regardless of floor level in fact, a wet location. My application is 3/4 PVC stubbed out under house panel and running 20’ to a kitchen island where I ran 2 12/2 NM cables for receptacles and equipment, WITHIN the slab. The slab in our northern environment is on top of a vapor barrier and 4” of foam….and heated, but for the sake of this discussion the vapor barrier is all that is pertinent. In my mind perfectly fine but I have read older threads on this site where many seem to agree with the inspector.
As I see it , the code uses Direct Contact With Earth frequently, it means just that, Direct contact with Earth, it is not.
Is it Damp? I don’t think so. A crawl space is damp and the obvious norm is running NM cable through it, what makes it NOT damp…Vapor barrier.
Is a PVC pipe stubbed out at both ends even a race way for what it matters, I don’t think so.
If there is some concern about the paper wicking moisture(inspector's idea) again I believe it’s a dry location, as silly as it sounds is there anything keeping me (other than the inspector) from gluing a couple of female adaptors on the pipe, stripping of the cable’s sheath for that part of the now ”raceway” and moving on? NOTE* though THWN is not printed on the individual conductors it is part of the labeling requirements for Type NM cable.
I would appreciate other Inspectors thoughts. Thanks.
 
Snowbound said:
I would appreciate other Inspectors thoughts. Thanks.
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334.12 Uses Not Permitted.
(A) Types NM, NMC, and NMS. Types NM, NMC, and NMS
cables shall not be permitted as follows:

(9) Embedded in poured cement, concrete, or aggregate
 
Snowbound said:
As I see it , the code uses Direct Contact With Earth frequently, it means just that, Direct contact with Earth, it is not.
Is it Damp? I don’t think so.
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If the slab is not in direct contact with the earth then the inside of the raceway is not a wet location. I didn't run the numbers but two 12/2's in a 3/4 seems like the raceway is overfilled. You're only allowed 31% fill for the two cables.

Location, Wet.
Installations underground or in concrete slabs or masonry in direct contact with the earth; in locations subject to saturation with water or other liquids, such as vehicle washing areas; and in unprotected locations exposed to weather. (CMP-1)
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infinity said:
If the slab is not in direct contact with the earth then the inside of the raceway is not a wet location. I didn't run the numbers but two 12/2's in a 3/4 seems like the raceway is overfilled. You're only allowed 31% fill for the two cables.
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Thank you Rob. I agree , not a wet location. The PVC is not a raceway, conduit fill does not apply though. Easy pull.
 
letgomywago said:
Is it worth it to you to do it that way? I've always tried for a 4 square at 18 inches behind the fridge or stove and feed with thhn from that when in a slab.
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Thanks Letgomywago, that’s another way that might be more practice in your case but for me they were two home runs 20 feet away and took me 6 minutes.
 
augie47 said:
I don't understand "PVC is not a raceway"... ??
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a Raceway is a complete piping system terminated with fittings to boxes and such. Another example would be coming out of a meter/main at ground level up the side of the two story to the attic and through to a new panel. You’re using service cable and run it in Whatever pipe you like from the eve to the panel for physical protection. That pipe is not a raceway.
 
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Snowbound said:
a Raceway is a complete piping system terminated with fittings to boxes and such. Another example would be coming out of a meter/main at ground level up the side of the two story to the attic and through to a new panel. You’re using service cable and run it in Whatever pipe you like from the eve to the panel for physical protection. That pipe is not a raceway.
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If I'm following correctly.
Since the PVC is not connected completely. It is considered sleeved.
If so sleeved NM does not need to comply with location.
 
Tulsa Electrician said:
If I'm following correctly.
Since the PVC is not connected completely. It is considered sleeved.
If so sleeved NM does not need to comply with location.
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It doesn't need to comply with all the rules but conduit in slab is considered a wet location. This is a dead horse issue where I'm from. Uf would work and be legal or just do boxes at both side which is the better way of doing this. Or pvc jacketed mc but that's more expensive than uf but it's less labor intensive than uf to strip and doesn't need sleeving to island outlet boxes
 
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