Wire running perpendicular to floor joist.

[Randy Phillips]

In my finished basement I am running wire above a drop cieling and have a question. I stapled the NM wire to the bottom of the floor joist and it is ran perpendicular. Is this within code?

[Hank Spinnler]

I pulled out my copy of NEC and in article 334.15(C) In Unfinished Basements and Crawl Spaces. "Where cable is run at angles with joists in unfinished basements and crawl spaces, it shall be permissible to secure cables not smaller than two 6 AWG or three 8 AWG conductors directly to the lower edges of the joists. Smaller cables shall be run either through bored holes in joists or on running boards. NM cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing or shall be protected in accrodances with 300.4."

I don't know of a code reference discussing wiring above finished drop ceilings. Support via staples not to exceed 4 1/2 ft. Flat cables should not be stapled on edge.

[Randy Phillips]

I assume a running board would be a plank nailed to the joist and the wires stapled to the board? Or would it be a board covering the wires?
Thanks for your advice on this as I want to ensure this is conforming to the NEC.

[Hank Spinnler]

Wires stapled to the underside of a 1x4 or 1x6 board.

It would be different if you had a situation like an attic where the wires are subject to physical damage. For example, while accessing an area of the attic to service HVAC equipment, you would need to staple the wires to the sides of boards to prevent potential damage.

[Randy Phillips]

thanks