NM in 5-Story Bldg.?

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tedge

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Camden, ME
I got a bid package today for a total remodel of a 5-story, multi-use brick building. It specifies NM cable as the wiring method. Now, I remember at some point there being specific wording in the NEC about no NM in 3 or 4 story (or higher) buildings, but it is not in Art. 334 of 2005 or 2008. What is there, is a bunch of gobbledee-gook about construction type, etc. Someone tell me that I'm not crazy, and that the owner of this building is about to find out that it's going to cost him a whole lot more for his electrical than he thought.
 
Yep I thought it was 2 1/2 story and less....and other stipulations?? not a place of assembly or something...I'll have to look that up
 
With a brief look at Annex E, it sounds like the outside walls and structural framing need to be non-combustible to make it 3,4,or 5 construction? Forgive my ignorance, but wouldn't roof framing be structural? The outside walls are brick, but the roof framing is old wood.
 
I wonder which wire manufacturer was on THAT cmp they must have dropped some serious persuasion techniques to push that one through. Persuasive speaking I presume.
 
Just don't forget that if there's any suspended ceilings involved, you're still gonna have to use MC or pipe in those ceiling areas. Additionally, I can't really see a way to run any exposed romex in a mixed use occupancy. Gotta have it all covered up by some means.
 
I wonder which wire manufacturer was on THAT cmp they must have dropped some serious persuasion techniques to push that one through. Persuasive speaking I presume.

Why....NM-B is a perfectly fine wiring method if properly installed. You're not from Chicago are you:rolleyes:
 
I live in Maine, and the State has chosen not to adopt the no NM over suspended ceilings bit. Guess I'll have to call the State inspector, as there are no local inspectors in this town.
 
I got a bid package today for a total remodel of a 5-story, multi-use brick building. It specifies NM cable as the wiring method. Now, I remember at some point there being specific wording in the NEC about no NM in 3 or 4 story (or higher) buildings, but it is not in Art. 334 of 2005 or 2008. What is there, is a bunch of gobbledee-gook about construction type, etc. Someone tell me that I'm not crazy, and that the owner of this building is about to find out that it's going to cost him a whole lot more for his electrical than he thought.

Bid it like the spec's. call for. Check local or state codes if it turns out you cannot use nm then its a change order. $$$
 
Bid it like the spec's. call for. Check local or state codes if it turns out you cannot use nm then its a change order.

Yeah, I guess I could do that. I don't like to operate that way though. I'd rather give the GC a price for what the job is going to be. I'll make it clear in my proposal what it is and why, and that anyone who bids differently will be back for a CO. Maybe that's naive of me, but I've tried to run my business that way from day one, and I've won many jobs that way. It shows that you've done your homework and know what is going on.
 
Maybe that's naive of me, but I've tried to run my business that way from day one, and I've won many jobs that way. It shows that you've done your homework and know what is going on.

Also a good way to develop and keep a relationship with a local GC. I've seen things from "their side" and know in MANY cases low bid does not get the job. (unless it's gov't) The relationship at that point is priceless.

I would think the AHJ would be the way to go on something like this. It seems to me NM rules can be flakey from location to location. Personally I dislike (true feelings censored out of respect) the stuff, and wish it was (more commonly) available w/ a stranded conductor.

My 2?,
Doug S.
 
You wanna share your thoughts on why NM should not be permitted?

Sure I will share.
Mostly because a more commercial building GENERALLY has more grounded materials involved in them such as metal studs metal ceiling grid metal doorbucks metal screws everywhere metal floor saddles metal doors metal pencil rod OR metal wire to hold such ceiling grid or ceiling blackiron to hold sheetrock.
This is all usually supported by steel I beams which are connected to the conductive concrete floor which is connected to the stuff we call dirt which is not such a good conductor as copper but anyone with some mathematical background can tell you what happens to resistance when you put the infinity sign under the single resistive path to ground.
Bolted steel I beams 5 stories high poured concrete for a floor at least the first one or even the basement only.
All of this weight pressing in direct contact with the earth (kind of sounds like a ufer at this point) All tied to the steel framework up 5 floors could pose an electrocution hazard to someone.
You think romex strung across steel hat channel might get knicked and energize a strip of ceiling grid waiting for some unsuspecting jerk to come along and complete the path just so the landlord can save a few thousand bucks on his install?? There is no defence for the inevitable hack who will have some method to duck a proper inspection. Not all electricians posess a conscience from what I have seen.[/I]
 
There is no defence for the inevitable hack who will have some method to duck a proper inspection. Not all electricians posess a conscience from what I have seen.[/I]

Ahhhh...the old "straw man" argument. I should have known. ;)

There's hacks who install MC cable wrong too...so we should ban that. Also, sometimes the same hacks don't install EMT right either...ban that too...in fact I can't think of a single wiring method that can't be hack, so let's ban all of them. ;)
 
Sure I will share.
Mostly because a more commercial building GENERALLY has more grounded materials involved in them such as metal studs metal ceiling grid metal doorbucks metal screws everywhere metal floor saddles metal doors metal pencil rod OR metal wire to hold such ceiling grid or ceiling blackiron to hold sheetrock.
This is all usually supported by steel I beams which are connected to the conductive concrete floor which is connected to the stuff we call dirt which is not such a good conductor as copper but anyone with some mathematical background can tell you what happens to resistance when you put the infinity sign under the single resistive path to ground.
Bolted steel I beams 5 stories high poured concrete for a floor at least the first one or even the basement only.
All of this weight pressing in direct contact with the earth (kind of sounds like a ufer at this point) All tied to the steel framework up 5 floors could pose an electrocution hazard to someone.
You think romex strung across steel hat channel might get knicked and energize a strip of ceiling grid waiting for some unsuspecting jerk to come along and complete the path just so the landlord can save a few thousand bucks on his install?? There is no defence for the inevitable hack who will have some method to duck a proper inspection. Not all electricians posess a conscience from what I have seen.[/i]

What happened to bonding the building steel? The same could be said for someone pulling wire in conduit. Did they clean the cut end good as to not leave a burr to nick the wire. Any install can be a good one or a bad one
 
Bid to the plans

Bid to the plans

If this is a commerical job. Where I am from the architec has to have them reviewed by an electrical engineer then submitted to the city for approval. If this print has been through the hands of these people bid to the plans, once you get the job raise your questions. Their are large companies out there with estimators, all they due is spit out quotes using one of the available estimating programs. Make cheap assumptions, use appropriate bidding disclaimers. For example on this small TI, GC called up after rough and asked if we would put in pulling conduit and boxes for fire strobes. I said didn't you read my quote that was not included for one I did not get a copy of the fire page for bidding, so why would you assume I would do that. This has not caused me to lose any GC's because in the grand sceme of things as long as you show up when you say, and are not the trade that is holding up progress than your good.
 
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