Here's my project, looking for oversights. Thanks !
Recently upgraded the main panel from 60A Federal Pacific to 200A CH, passed all local inspections. Then, National Grid upgraded overhead from pole to POA. 21 single pole slots remaining.
The main panel was upgraded so the garage could be isolated with it's own sub. Today, the attached garage and adjacent room share a single 15A circuit !!!
New garage sub panel (HOM12L125C) is rated for 125A, room for 12 single poles. Planning on a 60A breaker in the main, but want wire large enough to support 100A in the future. The choice of a 60A breaker in the main is the price difference for the 100A breaker ($15 vs $94) and current requirements.
Part of application is through a crawl space under the adjacent room, presently 12 ft of 1.5" schedule
40 conduit. Conduit is suspended from the floor joists (three feet above grade). Crawl space is insulated and considered part of main house envelope, plastic over the earth.
Between crawl space and main panel is basement.
I am planning to pipe and wire the whole thing from main panel to sub panel (68 feet) as follows:
Three THHN #2 copper (black, white and red)
One THHN #6 copper (ground)
Ground in sub panel will be isolated (not bonded with neutral).
No need for 240V in the garage at this time. Planning for three 20A circuits (outlets) and two 15A circuits (lights).
Will be talking with AHJ in next few days...