National Electrical Installation Standards

Standards as High as Your Own

Wednesday, June 20, 2018


I'm in Tennessee. I have a newly finished 3br/2ba house. 200A service. I have a small garage that I'm trying to bring power to. I have four spare breaker spaces. I was planning on adding a 150A sub panel in a detached garage using direct burial cable and spare breaker spaces in the house panel. My question is, will I need to mount a meter-base on the exterior of the garage and bring new service instead of just OCP'ing the 150A with a breaker inside the house panel, a disconnect outside the garage, and another 150A main breaker inside the subpanel? Some local guys told me that since the garage isn't ATTACHED it has to have it's own meter, which kind of defeats the purpose of using the spare breaker spaces. I'm trying to keep from doing this work twice

Zach Davidi



Hey Zach thanks for your question. Buildings and structures can be supplied by services or feeders or branch circuits by using Article 230 or Article 225 - unless there are local requirements that change that. The NEC does not require meters, those are required by utilities because they want to charge for the electric supply and usage. If the house service panelboard is suitable for the additional load of the detached garage using a feeder to supply the garage is acceptable. make sure you locate the garage panelboard to comply with 225.32. That is a very common practice.

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