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Attic subpanel

1199 Views 12 Replies 5 Participants Last post by  wraunch
I am finishing out about 900 sq ft of my second floor that is currently being used as attic. The framing is complete. I will have a 18.5'x30' theater with a wet bar and a bedroom in this space. I currently only have a 20 amp GFCI outlet and some keyless lights that are on a shared circuit with my second floor lights. I would like to run a 90 amp sub panel into an unfinished storage space adjacent to the theater. My plan is to run the wire up from the subpanel to the ceiling joist, down that to the edge of the house, out of the soffit and straight down the side of the house, then punch into the crawl space and come out right under the existing 200 amp service panel. The section from the soffit to the crawl space would be run inside of 1 1/2 PVC conduit. Do I need a J box at the soffit and at the bottom when it goes into the crawl? My big question is what size and type of wire do I need for this? I might only wire up 80 amps but I would like to leave myself some headroom so just pretend it'll be 90 amps now.
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I don't think there is enough space in the main panel for 100 amps. Believe me I want as much as I can get.

Here's my layout. I need at least 1 20amp dedicated circuit going to my equipment in the theater.

Floor plan Plan Artwork Drawing
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I have not done a load calc. That statement was just based off of 3 electricians that cane to bid the job telling me they though the max available would be 90. I don't know exactly how many amps I'll need.
How many amps will I need for this space? I calculate 23 6"cans, 14 3" cans, 2 fluorescent fixtures, 7 keyless fixtures, a counter height refrigerator, a countertop microwave, a 20 amp dedicated circuit for my av equipment, whatever I need for the wall outlets, and outlet in the tray ceiling for my led rope light. Based off that I calculate approx 3500 watts of lighting, plus say 15 amp for fridge, 20 amp for av rack. I'm thinking I'll need 80 amps. Thoughts?
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