connecting electrical to new outbuilding
I’m figuring out how best to connect electrical to a new, multi-purpose outbuilding. Currently our electrical service entrance is at a drive shed about 300′ from the house. It’s 200A service, with 250MCM direct bury cable at a depth of 3′ from the drive shed to the house. The new building will be between the house and the drive shed, about 20-30′ from where the underground cable passes.
I’m toying with two ideas.
1. Split the cable about where it passes the new building, and splice in another cable leading to the new building. Then run another length of cable from a splitter box in the new building and splice it to the other end leading to the house. Downside of this is I think it might require the splice to be accessible, which I wouldn’t be too thrilled about.
2. Same as above, except cut the cable at a point far enough past the new building that it can be pulled up and reach the new building without a splice, then connect a new length of cable from the splitter box to the house. This would be significantly more work because of the landscape around the house; the wire goes under a compacted gravel parking pad and landscaping gravel around the house. It’s probably 4′ deep right at the house. It’s a slab on grade and the cable enters from underneath the slab, not the more commonly seen conduit running up the side of the wall.
3. Another option, which I’ve almost completely discounted, is to run new service from another power pole to the house, then run a cable from the house to the new building. This would be a massive amount of money due to the involvement of the power company and the length of cable they would be running. It would also probably result in moving the panel in the house to accommodate a different entrance location, another expensive and logistical nightmare.
Am I missing any other options? I’ve ruled out running another cable from the house to the new building because it has all the downsides of option 2, plus having to locate a splitter box inside the house and reroute some interior wiring for it. I’m also expecting the new building to use at least as much electricity as the house in the future (e-vehicle charging, big woodworking equipment, etc.), so it’s not great from a voltage drop perspective).
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