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Sub-panel installation

Hi all. I'm thinking about installing a 2 breaker sub-panel in my attached garage, so I can expand the number of outlets and add additional light switching options. I was looking at using a 20-amp breaker for the outlets, and a 15-amp for the lights. My initial thought was to use a 40-amp double pole breaker in the main panel to feed the sub-panel. I'm wondering if I can get away with using a 30-amp feeder, or should I stick with a 40-amp. And, what type of wire gauge would be appropriate for each? Thanks.

Re: Sub-panel installation

It depends on what you plan on running.

Re: Sub-panel installation

With a 20 amp outlet circuit and a 15 amp lighting circuit, I doubt you will ever exceed 30 amps. 5 100 watt lights would draw less than 5 amps. You would need to use 10 ga for a 30 amp drop. My suggestion though would to put in a little larger 240 volt sub panel and service in case you want a workshop in the garage later or want to add heaters.


Re: Sub-panel installation

Thanks for the advice, and I should have clarified. I use the garage as my primary "workshop," but I do not heat it. While I have a compound miter saw, table saw, router, and many other basic power tools, there is almost never more than one operating at once.

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