Existing Slab PVC Pentetration

[Wiregirl]

I have looked at a job today for a wood frame residential garage. The slab was already poured and is over a foot deep. The homeowner had told the contractor the poured the slab to put a pipe sleeve in the slab for the electrical feed. It is a 1" schedule 40 white pipe.
Can I make the transition to grey schedule 40 from the slab out, and still be in code? The feed will be direct burial, through the slab and into a small breaker box.



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[MNSparky]

White plumbing pipe isn't listed as an electrical raceway so using it as one wouldn't be NEC compliant. The only way you would be able to use it is if you could fit an electrical raceway through it. Since it's only 1", good luck with that. You're probably looking at the standard up the outside and LB'ing into the building.

 

[Coppersmith]

Since the wire is direct burial type (UF I'm assuming), I think it would be legal to go through the white pipe since it's just a convenient hole in the slab. Once you emerge from the slab inside the building, if the UF is inside a wall, it doesn't require conduit so attaching a grey pipe to the white pipe is not an issue. If it's exposed and not protected by the studs, you can still sleeve it with PVC sched 80 without a formal coupling, just slide the end into the white pipe chase or butt it up against as long as the sleeve is firmly fastened in place. You could also cut the white pipe flush with the deck and set a box over it to transition to conduit if necessary.

I would be concerned about whether there are any sharp 90's in the white pipe run. That would be hell to pull through.

Not sure if there is a burial (cover) depth issue here for where the cable comes into the slab from outside.

 

[tom baker]

And your building may require a ufer ground unless its a single branch circuit, and there is no reinforcing steel in the footer

 

[peter d]

White plumbing pipe isn't listed as an electrical raceway so using it as one wouldn't be NEC compliant. The only way you would be able to use it is if you could fit an electrical raceway through it. Since it's only 1", good luck with that. You're probably looking at the standard up the outside and LB'ing into the building.

Chris,

That's true if individual conductors are used. But, direct burial cables or conductors can be installed in any kind of pipe.