A.Joe Tedesco, a licensed electrician, a certified electrical inspector, and the moderator of JLC Online's electrical forum, responds: In general, the NEC doesn't permit service-entrance conductors to pass through the interior of another building unless they are protected by brick or concrete, or a specially constructed vault.

But in your case, as long as the conductors are enclosed in conduit and are buried at least 18 inches below grade, the NEC would consider them to be outside the building (2005 NEC 230.6[4]).

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