Quote Originally Posted by Allan Speers View Post
OK, but I already have the #6 Romex, and I still like the idea of having a metal protector around a 220 line. Taking into consideration you point about heat, would it not be OK to use an oversized conduit, say 3/4", and leave small gaps every few feet? (Or maybe even drill heat holes on the "top" surface of the conuit.)
Allan, it's your house and your call. I would never do it. I've seen too many unexplainable things happen. Certain rules of the code were created because scientific proof, testing or personal experience dictated it.

If I had the romex and it met code in my area, I would install it according to local code. You may be able to install it through the joists. That would at least put it in a place somewhat protected. But it's ultimately your decision.