National Electrical Installation Standards

Standards as High as Your Own

Wednesday, April 11, 2018


Where can I find in the NEC the area that explains that it is not allowed to run the service line at the house from the weather head to the electric meter behind aluminum siding trim?

Steve Harris



Hey Steve thanks for your question. There is not specific wording that prohibits service conductors from being behind aluminum trim as you describe. The service disconnecting means must be outside or nearest the service conductor entrance point as stated in 230.70(A)(1). Although the conductors are not literally entering the building if behind trim they do not seem to meet any of the conditions of 230.6. Protection from physical damage could be a concern as stated in 230.50(B) and if Type SE cable 338.12. Also keep in mind these conductors do not usually have overcurrent protection, based on their ampacity, on their supply side. The decision is up to the AHJ.

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