I am asking in reference to articles 382.2 & 382.12 in the 2008 edition of NFPA-70.
The following definition appears to me to be describing Romex (NM-type) cabling:
**382.2 Definitions**
**Nonmetallic Extension.** An assembly of two insulated conductors within a nonmetallic
jacket or an extruded thermoplastic covering. The classification includes surface
extensions intended for mounting directly on the surface of walls or ceilings.
Then, this article indicates that nonmetallic extensions cannot be used in attics:
**382.12 Uses Not Permitted.** Nonmetallic extensions shall not be used as follows:
***(1) In unfinished basements, attics, or roof spaces***
(2) Where the voltage between conductors exceeds 150 volts for nonmetallic surface
extensions and 300 volts for aerial cable
(3) Where subject to corrosive vapors (4) Where run through a floor or partition, or
outside the room in which it originates
My home is a single-family dwelling with a single floor, an unfinished accessible attic (permanent ladder) with crawl space only, and an unfinished basement.
I was hoping to be able to use Romex to connect branch circuit junction boxes in my attic with runs along the floor joists and through the floor joists (existing bored holes from knob and tube). I was also hoping to be able to use Romex with runs along the ceiling joists and through the ceiling joists in sections of my unfinished basement to connect junctions and light fixtures. However, these articles appear to prohibit the use of Romex in unfinished attics and basements. Must I use MC or AC for this application or am I misinterpreting the definition of a nonmetallic extension? Or, is there an article that I am missing that makes plain Romex acceptable for these applications?
Also, if it is not acceptable for these applications, how should I deal with getting runs of Romex down from the attic (or up from the basement) to power receptacles in the finished portion of my home? Is there an acceptable defined length for which NM cabling may be run in the attic to reach from a junction in an unfinished attic to power a wall receptacle, or is the only way to be code-compliant to just run AC down to the first (metal) receptacle junction box and run Romex through the walls to the other wall receptacles in the room?