While I'm an advocate of not upgrading to a 200 amp service when it is not necessary. Depending on what you are doing, your service may be pushing adequacy. The size depends on what it is for. If you are adding some circuits on that side of the house for general lighting and appliance use, the panel does not need a large feeder. It would be kind of silly to put a 100 amp sub panel feed in when the entire service is 100 amps. Most likely 8/3 with ground or 6/3 with ground will be fine. If the sub panel is for a more substantial load such as the addition of large kitchen appliances, a shop with heavy loads, or other large loads. you may need a 100 amp sub panel and if the main panel has a good amount of items on it already, you may be better with a 200 amp service. The sub panel only has to have a rating the same or larger than the breaker protecting the feed to it. IE: You will most likely be using a 100 amp sub panel with 40 amp 8/3 wire connected to it, etc.

kzaker you need to post a NEW thread, rather than asking your question in the middle of someone else's. I don't immediately recall how it works out but I have encountered many services, including recently-installed-and-apparently-approved ones, consisting of a mobile-home-style "meter main" or CSED (meter socket and main circuit breaker in one box) feeding regular old SE cable (NOT SER). ie, 3-wire. Given how many of these my local power company has apparently approved, I am inclined to believe this is legal in some certain scenario. Further, the apartment complex I grew up in, consisting of four buildings of six units each, which is wired very well (other than having FPE breakers - which weren't perceived as a problem back then) is also wired the way the original poster describes. Power comes in to a little shed on the end of the building, which contains six meter sockets with built-in 100A circuit breakers. 3-wire cables leave these sockets and go to the apartments' individual breaker boxes, which are wired as MAIN panels. I'm moving a service within the next couple weeks. The power company guy came out and looked at where I want to put the meter, and approved it. As part of our conversation, he stated that if I put the panel where I originally wanted it, I will need an outdoor disconnect due to distance (2 feet??!!). Supposedly I can still use SE, however. When is a panel fed from an outside disconnect considered to be a subpanel? Unless I'm surrounded by illegal services, it sometimes isn't. What's the distinction? I think the original poster's existing wiring is probably correct.

Sure thing. I think I will be safe considering IT ISNT LIVE. And my kids wont be killed because IT ISNT LIVE. And considering that I have already said that I would absolutely have it all checked before it is finalized  I think all will be well. Oh, about the hot Âtub  I didnÂt mean to insinuate that it is hooked up now. I have only used it a few times, I donÂt have it hooked up on a permanent basis. But the pool on the other hand, I really want to get that addressed but it would be easier to address that after the garage is figured out because it is half way to the pool. I do run that off of an extension cord, but only once a week at the most, and I never do it when the pool is in use because of my fear that the cord would get wet. So I hope you understand that I am looking to have it all done the right way, but I canÂt do it all at once. I guess the first step is the garage; like you had said.

Are you sure you need 100A in the garage? For a small, one person workshop, a 60A feed should be sufficient. If 100A is needed, you can run three #2 Cu and a #8 Cu OR three #1 Al and a #6 Al. The aluminum will be cheaper but you must use antioxidant paste at the terminations with Al. Remember, you will also need one or two ground rods at the garage connected to the grounding bus with #6 or #4 Cu.