I have a question about a service panel connection... I need to get power to the upper floor of my home. I plan to replace the Romex running through a conduit on the outside of the wall up to the attic with individual wires. You might be able to see the conduit running up the tall wall on the right between the two drafty windowsl in the picture. There are three things going up the wall. Power (3/4" rigid conduit), gas pipe, and A/C coil drain pipe. The conduit goes into the house through the wall and is terminated at either end just inside the walls with a bushing. The "bare" Romex then runs along joists to the main panel downstairs, and to a junction box in the attic. My plan is to remove the romex from the conduit and replace it with 7 12ga. wires (three black, three white, and one ground) to increase my circuits from two to three upstairs. I will attach a piece of flex conduit to the end of the rigid and extend the conduit over to the junction box in the attic. In the basement, I would do the same...attach a piece of flex conduit to the end of the rigid just inside the wall and run it over to the back of the main panel. Of course, I know that I need to encase the individual wires in something through the open attic and open basement... So, long introduction for a "simple" question: Can I run flex conduit from the back of the main panel through my basement (attached to floor joists) and attach the other end to the rigid conduit, or do I have to use rigid conduit for this purpose? I live in CA, in case that makes a difference... TIA.