I'm planning on installing a 100amp sub panel in the garage. The garage is right around the corner from the main load center in the basement, but part for that path goes through the stairway from the garage into the basement. I think it might be required or at least a good idea to have the wire protected in a conduit for that part of the run.
I am planning on using 1/0-1/0-1/0-2 Al SER wire for the run.
Should it be in a conduit for some or all of the run? What size if needed?
The total run should be about 30 feet with going around bends.