ECN Forum Forums Code Related Discussion NEC & other Code issues Romex in commercial buildings?

macmikeman,
Yep, never seen rat damage on MC or pipe. I have found a dead rat locked on to 12/2 romex.

"E"

The grocery stores we wire certainly have more than 100 people in them quite often, that does not make them a place of assembly.


Look carefully at the examples of places of assembly in 518.2(A), they are not simply buildings that hold more than 100 people. They are places where more than 100 people are expected to be densely packed.

The added smoke danger presented by NM to the building occupants is only the additional smoke generated from the jacket. We can not count the insulation on the conductors as this is present in MC/BX/EMT etc. Even though these conductors are in metal raceways they will generate smoke that will leak out of boxes and fittings.

But here is what gets nuts in my opinion, the wiring methods in a typical building only form a very small percentage of the smoke producing products in the building.
Also the wiring methods are spread out mostly in walls and ceilings.

What about the rug that is everywhere, the furniture, the typical plastic stuff that is through out the building? These items are actually 'in' the same spaces that the people are.


Well seeing as you said you have a PM it is not up to you.

You want to make decisions like this you will need to run your own company.


Nothing makes a theater different from a church, both may have portions that may be NM and both may have portions that must not be NM.

Bob

I think I would require pipe/flex in any occupancy that could reasonably expect major revisions or renovation within 5 years, and I wouldn't expect different as an EC.

Look at the average lifespan of a strip mall occupancy... IMHO, the use of NM in such an occupancy would lead to all sorts of rat's nests from abandoned wires from the prior occupant when the (non-english-speaking low bid psuedo-)EC working for the landlord/management company does a rush job for the new tenant.

E57,

I don't deny for a second that NM cable is more flammable, you are absolutely correct. And yes the rats chewing on the insulation is another issue to consider, but it doesnt weigh heavily on my mind, as rat infestation speaks of other serious problems.

Consider this. A few years ago there was a devastating fire at The Station nightclub in West Warwick, RI (my home state.) The entire building was consumed by flames in less than 3 minutes, and 100 people died as a result. Numerous others were severely burned and disfigured by the blaze.

The nightclub could have been wired entirely in RMC and it would have made no difference in the spread of the fire. The main contributing factor was highly flammable packing foam that had been put on the walls for sound deadening. This, of course, was a serious code violation but not an electrical one.

So the point is, as myself and Bob have both mentioned, once you fill an occupancy with toxic-laden combustibles, the wiring method quickly becomes irrelevant in my opinion.

Peter

edited to add: The Station fire ushered in a total overhaul and complete revision of Rhode Island's fire code. It is now one of the strictest fire codes in the nation.

[This message has been edited by CTwireman (edited 09-15-2004).]

Doug I mean no ill will at all, but I want to ask what your experience with NM is?

I believe you are in an area that pretty much denies the existence of the product.

I have grown up with NM and our buildings are not predominantly rats nests. NM just like pipe can be installed, modified, maintained in a neat and workmanlike way or it can be all hacked up. IMO it is the tradesman not the product that has the biggest influence on the job.

JMO. Bob

Bob,

No offense taken, or meant.

What I was suggesting is that, when an occupancy is vacated, and then customized for another renter with a different type of business that requires less outlets and KVA (say former pizza joint turned boutique, or hair salon turned record store), the temptation will be there for a fly-by-nighter to simply "abandon in place" and re-wire for the demands of the new occupancy. With NM this can be much uglier than a raceway system.

I wasn't saying that NM by itself in all installations is a rat's nest. Trust me, I've seen enough crooked EMT and kinked MC to know that what you say about quality being the tradesman not the product is gospel.

BTW, although the lake shore communities of Lake County do tend to ignore the rather plebian NM cable family , I rewired an old K&T house in Kenosha, WI using NM along the old wire runs. I've also used it in Milwaukee at my ex (thank God!) GF's folk's place, and in my Mom's in Decatur, and my wife's folks in St. Louis, Mo. Not a lot, compared to many of you guys who run it on a daily basis, but enough where I do recognize it's versatility and usefulness.

[dig] I still love my pipe, though! [/dig]

I had no idea that anyone was concerned about the smoke toxicity of NM...very interesting. I'd always assumed that it wasn't allowed because it's such a wimp in the class of physical protection of the conductors. In this area it's allowed in the county, but not allowed in the city jurisdictions.

I run so little of it that I don't keep it in the truck. Part of it may be that it seems like cheap materials for low-bid work. It's not the type of business that I go after. When I run NM I feel like a weekend warrior, when I run EMT I feel like an electrician.

Dave

Doug

Cool

Dave I am no weekend warrior.

What do you guys do to the NM that it is so likely to be damaged?

Weekend warrior?

Here,there are FEW commercial buildings,and the most of them are wood-frame.

We do mostly residential,because that's what there is to do. We'll do a small commercial job sometimes,mostly small office spaces. I'd like to pipe all of it,but there's no way.

The homes we do are mostly in the 4-8000 sq.ft range.


We've done a couple small resturants in the last couple years,and ran Pipe and MC cable.

With no permits or inspections for the majority of it, We have to bid against the $12 and hour guys. Most of them wouldn't know a stick of emt if it bit them,but they get a lot of the work.

An NM-B job can be done neatly and safely as anything else imho,and it has a good track record here. It's good if you can pick and choose work and do all commercial,but we don't have that option unless we move someplace else.

Russell

Chill guys, I said I feel like a weekend warrior when I run NM, I'm not saying anything about anybody else.

Of course it's easy enough to run NM without damaging it, but having my circuits surrounded by steel makes me feel all warm & fuzzy inside, as well as those larger bank deposits.

I ran 4 circuits across a house this week in one conduit, and I'm not sure there would have been any great savings in running (4) NMs.

Dave