ECN Forum Forums General Topics of the Trade General Discussion Area Plastic or Steel?

I can't imagine a 100,000 sq.ft.bldg.wired with type nm.It would be emt here.

John, we do this in MA and RI
Not a plenum ceiling, hard duct returns.

Per job spec No NMC visible, EMT in mechanical spaces.

But pop a ceiling tile and all you see is NMC, 10/3 NMC = 30 amp 480 volt feed to RTU

If you're asking about "Places of Assembly"

It does not seem to qualify. ????

At plan review, some towns in MA have Bylaws you have to follow. This is all settled by the customer's lawyers. They build 18 to 25 new every year so they know the ropes, and how to bully small Towns

"Don't Give us a hard time we will go to the next Town over"

Bob

Iwire:
Thanks for the prompt reply.
Over here (NJ) that would not fly. If the NMC was on the plans, the job would not be approved. As to the "bully" thing, that wouldn't work either.
Take care.
John

txsparky, unfortunately we must bid to compete with the other ECs.

The time frame would prohibit a full pipe job, if they wanted it. With NMC or MC it takes a crew of 15 to 20 to get done in the 3 to 4 months we get from start to finish.

Isn't NM cable also more prone to be chewed through by rodents?

I wonder if that's why NYC demanded MC cable, since we do have a big rodent problem, especially with older buildings.

That would be a big factor for me to choose MC for all applications over NM.

Why is NM used for resi? Is it cost?

II have never NMC of modern construction chewed by rodents, the old stuff yes.

Cost, yes, I do not see prices that often but I think NMC is 1/4 to 1/3 the price of MC
I am sure someone here could be more accurate with price. You can install it much faster; use plastic boxes if you want.

But I would rather use MC in most applications

As far as timber-framed houses go, plastic is your only real option over here.
But with concrete or brick walls, we tend to use the steel type, as these are a lot easier to use with conduit.

Being a Commercial Installer / Designer, I rarely get the chance to use any PVC Outlet Boxes. Only in some underground floor box situations do I deal with PVC boxes (or on a Custom House).

So, for my installs, mark me as a Steel Box user.

Scott s.e.t.

SvenNYC
The resi guys like NMC because of the following:
It's "CODE"
Cost
Easier to install
Utilize PVC boxes (no grounding of boxes)
PVC boxes are cheaper then metal
MNC is "lighter" then MC
Your hands don't get as dirty with NMC as MC

Resi builders utilize the most economical CODE COMPLIANT wiring> (And Fixtures)

Time to have dinner.
John
Edited at 9:15Pm; I was hungry and addressed it to Iwire by mistake.
John

[This message has been edited by HotLine1 (edited 01-14-2003).]

HotLine1, It was SvenNYC who asked

"Why is NM used for resi? Is it cost?"

Bob