ECN Forum Forums Code Related Discussion NEC & other Code issues Damp Location

Guys,

Will someone please CITE the NEC section
dealing with this topic.

Are we discussing the AHJ opinion
or
NEC requirements ?

2008 NEC....334.12 (B)(4) for starters; then 100 (Definitions) for 'damp' 'wet'.

AHJ's interpertations (opinions) are covered in 90.4 (Enforcement)

I have never seen NM-c (has anyone here?) but I understand it uses a plastic packing instead of the kraft paper.

Greg, I couldn’t swear that it was NMC, but years ago I worked in several homes that were wired with some form of white-jacketed NM cable that had TW conductor insulation and plastic filler strands instead of paper. These homes were probably wired sometime in the mid to late 70’s or possible the very early 80’s.

I agree that the claims of wicking or capillary action of moisture through the paper filler is BS at best under most all circumstances.
I’m pretty sure we’ve all seen it happen before, but it was always due to some installation issue other than just having the NM stapled above a gazebo or covered porch, crawlspace or a similar, arguably damp location. That is, at least in the situations where I have encountered it.

I agree.
I've read elsewhere though, that some inspectors actually consider that type of area as a damp location and won't allow NM to be installed there. That is the type of installation conflict I would like to see eliminated by the NEC allowing NM to be used in both dry and damp locations, but I realize this is not likely to happen with the product driven code we have today.

Years ago (1975-1980) I saw NM wire that had blue coated plastic sheath, I think it might have been NM-B or NM-C. (It was many years back and I can't remember back that far!) I did think that it was strange to have colored wire, little did I know that it would become the norm.

Harold, I remember that cable. It was standard NM and was made by Phelps-Dodge. What was equally unusual about it was that it often had a brown wire instead of black in it.

Cadillac Cable also made a version that had either green or brown jackets. No particular reason; they just felt like being different I suppose. I would hate the fact that you never knew what color it was going to be until you opened the box.

Sorry for the side track.

Harold:
You're jogging my memory...blue jacket NM, I believe it may have been Southwire or Colonial. I have a Colonial facility (THHN Only) in town....Tues/Wed of next week I'll ask the plant mgr IF he remembers...he came to town from the NM plant in NY.

The 'green' that Ed mentions sure would raise a few eyebrows with some inspectors I know!!

BTW, I like the colors!

Remember the 'good old days,' when 'yellow romex' was a mis-used extension cord?

I have an assortment of different colors of NM here. Some is silver asphalt/paper. The rest is white, brown, blue, black and the yellow PVC. I have pulled most of the blue, black and brown out because that was the previous owner's work and pretty dodgy. I am sorry I didn't save a piece of each one with the writing on it. I think it was the blue that had the color coded conductor metal. The black wire had copper colored conductor and the white was more of a silver color.
I may have only have 20 - 30 feet of the black. It looked like he bought a small piece to run one circuit.