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

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VirutalElectrician said:
How is replacing the wire for 2 circuits in a 20' run several hundred wasted dollars of material?
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It was two runs to an island and two runs to floor receptacles, one switched and I had to bring it to the switch box in the wall. Wire was 300 ish as local theft drove the price up. Yanking all the old out…as an update the inspector has decided all concrete regardless of floor is a wet area…🤔so now no MC cable through walls either…see how that goes.
 
IMO, the inside of the PVC in this case cannot be considered "wet".

Based on the NEC definition of "damp", it might be that it is "damp". There is a good chance of some condensation inside the PVC as the concrete may well be cooler than the surrounding environment and humid air could well enter the PVC pipe and condense.
 
Snowbound said:
It was two runs to an island and two runs to floor receptacles, one switched and I had to bring it to the switch box in the wall. Wire was 300 ish as local theft drove the price up. Yanking all the old out…as an update the inspector has decided all concrete regardless of floor is a wet area…🤔so now no MC cable through walls either…see how that goes.
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Also, why did you bill this mistake to the customer? Your install didn't pass inspection. The customer should get billed what the correct install would have cost, not the correct install plus the failed install.
 
VirutalElectrician said:
Also, why did you bill this mistake to the customer? Your install didn't pass inspection. The customer should get billed what the correct install would have cost, not the correct install plus the failed install.
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I would agree if the inspector was correct. If not, I would explain what's going on with the customer, and offer them the choice of simply complying at the customer's expense, or having their support in challenging the failure with a formal appeal.

In my opinion, it is just as wrong to fail an installation incorrectly as it is to pass one incorrectly.
 
LarryFine said:
I would agree if the inspector was correct. If not, I would explain what's going on with the customer, and offer them the choice of simply complying at the customer's expense, or having their support in challenging the failure with a formal appeal.

In my opinion, it is just as wrong to fail an installation incorrectly as it is to pass one incorrectly.
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I don't know if the inspector is correct or not. IMO, it is possible he is correct for the reason I mentioned in post #24.

However, I am not completely convinced one way or the other.

I think it is most appropriate to bring this up to his boss and see what his boss says. Not some kind of official complaint, just a friendly chat.
 
petersonra said:
IMO, the inside of the PVC in this case cannot be considered "wet".

Based on the NEC definition of "damp", it might be that it is "damp". There is a good chance of some condensation inside the PVC as the concrete may well be cooler than the surrounding environment and humid air could well enter the PVC pipe and condense.
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Between this section and the other are you trying to say that inside these conduits are not wet locations?

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
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300.9 Raceways in Wet Locations Abovegrade. Where raceways
are installed in wet locations abovegrade, the interior of
these raceways shall be considered to be a wet location. Insulated
conductors and cables installed in raceways in wet locations
abovegrade shall comply with 310.10(C).
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I am saying it is not "wet" because the OP stated the slab is not in direct contact with earth.

Whether it is "damp" or not, is something that seems to me to be up in the air.

IIRC, NM cannot be used in wet or damp areas, so if it is "damp" inside the PVC, it can't be used there.

My personal opinion is that it is "damp" because once you get some condensation the water has no place to go except to accumulate in the PVC.
 
I don't have the 2023 code handy, but a fellow EC was told in his CE class that the '23 does away with the requirement for receptacles on islands. BUT you still have to run either an unenergized 12/2 or empty conduit to the island in case someone wants to add them later. No receptacles on the sides either. All have to be in the countertop.

Was he right?

-Hal
 
hbiss said:
I don't have the 2023 code handy, but a fellow EC was told in his CE class that the '23 does away with the requirement for receptacles on islands. BUT you still have to run either an unenergized 12/2 or empty conduit to the island in case someone wants to add them later. No receptacles on the sides either. All have to be in the countertop.

Was he right?

-Hal
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This was added and I think they back pedaled to hard. If it was me I'd have an energized wire in the cabinet but capped off with a box and blank cover. If adding the outlets in the counter in the future it would be easier to get to it.
 
hbiss said:
I don't have the 2023 code handy, but a fellow EC was told in his CE class that the '23 does away with the requirement for receptacles on islands. BUT you still have to run either an unenergized 12/2 or empty conduit to the island in case someone wants to add them later. No receptacles on the sides either. All have to be in the countertop.

Was he right?

-Hal
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No receptacles on the side of an island. No receptacles required on an island, but provisions must be made if none are installed
 
petersonra said:
IMO, the inside of the PVC in this case cannot be considered "wet".

Based on the NEC definition of "damp", it might be that it is "damp". There is a good chance of some condensation inside the PVC as the concrete may well be cooler than the surrounding environment and humid air could well enter the PVC pipe and condense.
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It can’t be damp any more than a crawl space is damp with vapor barrier down , else millions of homes would non compliant. And…it is sitting on 4“ of foam in a heated floor. If the inspector is looking for wiggle room with his conscience.
 
petersonra said:
I don't know if the inspector is correct or not. IMO, it is possible he is correct for the reason I mentioned in post #24.

However, I am not completely convinced one way or the other.

I think it is most appropriate to bring this up to his boss and see what his boss says. Not some kind of official complaint, just a friendly chat.
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Unfortunately he is the new boss…should start another string but he (all five) insist on duct seal for single gang mail on boxes….just silly, wasteful non sense.
 
Eddie702 said:
My opinion FWIW is the slab on grade is considered a wet location and so isn't the inside of the PVC. No one can guarantee the vapor barrier is 100% or that the pipe is 100% dry.
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That I imagine is his thought. Wiring for 100% is impossible, but the code writers did not intend it to be considered it wet or there would have been language separating a ground floor slab with walls and countless upper concrete floors. this includes any time you drill a hole through concrete and stub out MC or romex for a light fixture.
 
#4 answered this by nec 100 definition. If it’s not in direct contact with earth tell inspector to pound sand. If he knows you fight back he will be less inclined to make crap up like this
 
Methinks plastic under slabs was not done when that code was written, and they should clarify whether plastic under a slab changes embedded conduit from being a wet location.
 
letgomywago said:
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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in the slab above a moisture barrier is not a wet location. I forget where, but there is an informational note in the code book that clarifies this.
 
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