What wiring method; your take?

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peter d said:
In that case I would guess that the appropriate code sections apply to each particular kind of occupancy within the overall building, but I'm just shooting from the hip here.
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I think your right (HEY! do I get Brownie points) a good example of that is "Assembly Occupancies" you could have a theater wired with MC in some areas and NM in others.
 
iwire said:
I think your right (HEY! do I get Brownie points) a good example of that is "Assembly Occupancies" you could have a theater wired with MC in some areas and NM in others.
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That's why the whole "wire the whole thing like a 'commercial building' " seems like it only comes from those that don't understand the specific code sections in the NEC.
 
mdshunk said:
The answer I got, in short, "Nope, the whole thing is a commercial building. No exposed romex above the suspended ceilings in the apartments".

Do you agree or disagree?
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I agree this is a 'commercial building'. Reason, I deal in real estate and ANY TIME you have over 4 "dwelling units" its considered a 'commercial' building by the banks and by most cities and 'municipalites'. Any time you have any 'mixed' use building, even if its 1 dwelling unit and 1 "general purpose occupancy" (ie storage, a store, a barber shop') its considered a 'commecial' building.

No you will NOT find this in the NEC, this is more of a local municipality call. Mainly for taxes. ;) At least this is how its interpet in my area.
 
peter d said:
In that case I would guess that the appropriate code sections apply to each particular kind of occupancy within the overall building, but I'm just shooting from the hip here.
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That's how it is locally here - to a point.... :wink: Depends on a several factors: (Mostly outside the NEC, and local electrical code.)
New building and muscle flexing inspector figuring out building type and envelope. Most new buildings for commercial are "Non-combustible" material - framing, wiring, etc.... And often tin can walls and concrete separation between the upper often wood framed 'dwelling' floors - nothing below that separation can be NM, as both the commercial unit, and the lobby or common areas are in the 'commercial envelope'. And no NM allowed in commercial by local code.

Older existing building in say wood framing.... (Like many are) nothing again can be NM below, or within the fire separation - i.e. below the sub-floor for above, as it counts as the rated assembly as a whole... Until the carpet/flooring or bottom plate on top of it....

Then number of floors total 4 and over = No NM, unless it is a single family...

Then there is "mixed use" units - total crap shoot on the mood of the Planning Rep, and any of the Inspectors. (Is it Commercial or is it Residential?) This it seems often comes down to the design of the floors and the Inspectors 'feeling' about its use... I once had to keep pointing to the words "Master Bedroom" on the plans to get a whole job through.... Who kept saying - "~looks like an Office to me."

To make things even MUCH WORSE - the "Committee Damned" the DAS of my state, split "Residential Electricians" off in a similar way - with additional conditions....
(2) performs work installing the required panel boards and feeders for commercial tenant space in a multi-family/multi-use occupancies falling under subsection (b)(1) above, where less than 50 percent of the first floor level is used for commercial tenant space, but not performing any tenant improvement for these spaces.
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Ref:http://www.dir.ca.gov/t8/290_1.html
 
brother said:
I agree this is a 'commercial building'. Reason, I deal in real estate and ANY TIME you have over 4 "dwelling units" its considered a 'commercial' building by the banks and by most cities and 'municipalites'. Any time you have any 'mixed' use building, even if its 1 dwelling unit and 1 "general purpose occupancy" (ie storage, a store, a barber shop') its considered a 'commecial' building.

No you will NOT find this in the NEC, this is more of a local municipality call. Mainly for taxes. ;) At least this is how its interpet in my area.
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While you are somewhat correct, I do disagree a little. We too consider multifamily dwellings as commercial buildings, but they can and shall be wired as a dwelling units.

So Marc is saying that he can us NM in the dwelling portion per 334.12(A)(2) and I do not disagree with that. My thought here is that (we don't see a lot of suspended ceilings here in residential) is that the space above these ceilings may be used as a plenum and that we do see here, especially in multifamily. There may also be a question about the common hallway (corridor) as to the F&T rating of the cable.
 
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mdshunk said:
I've inquired with the local inspection agency regarding the proposed wiring method.
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Is this inspection agency the AHJ or a private inspection company or what?

You could check with the Fire Marshal's office and see how they feel about it.

If it's an official ruling then I don't see that it matters all that much because everyone bidding the job will have to use the same wiring methods.

Much like the areas that require #12 NM only. If everyone has to do it then the added cost just get calculated into the bid.

All of the laws of our land are written by men and end up getting iterpreted by others. Judges don't always see eye to eye on criminal law so why would we expect other officials not to differ in opinions.

Just what is the meaning of "is"? The Clinton defense.:grin:
 
growler said:
Is this inspection agency the AHJ or a private inspection company or what?
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A 3rd party company, hired by the AHJ to perform electrical inspections. The actual real AHJ has no knowledge of electrical issues, and it would be pointless to inquire with them. The real AHJ is the town council, and doctors, lawyers and Indian chiefs aren't the people you want an opinion on this stuff from.

growler said:
You could check with the Fire Marshal's office and see how they feel about it.
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I could check, but that would be fruitless. The Fire Marshall's office in PA has no jurisdiction or even an interest in new electrical wiring in PA. They basically only investigate fires. The Fire Marshall works under the state police.
 
mdshunk said:
The Fire Marshall's office in PA has no jurisdiction or even an interest in new electrical wiring in PA. They basically only investigate fires. The Fire Marshall works under the state police.
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The states are so different, that is the polar opposite of MA.

Here the NEC is amended and adopted by "The Department of Fire Services"

90.4 is amended and tells us.

Interpretations go to "The Board Of Fire Regulations" and any appeal against an "Inspector of Wires" goes to "The Board of Electricians" which will then ask the "The Board of Fire Prevention Regulations" for a ruling.
 
iwire said:
The states are so different..
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Yup, in RI electrician licensing falls under the Department of Labor, while enforcement is taken care of by local and state officials, in CT licensing is handled by the Dept. of Consumer Protection, while enforcement is again done by local and state officials.

In RI as you know, all fire alarm work is inspected and approved by the local fire departments. The electrical inspectors do not even look at FA systems nor do they have any jurisdiction over them except for the line voltage parts of them.
 
peter d said:
Yup, in RI electrician licensing falls under the Department of Labor, while enforcement is taken care of by local and state officials, in CT licensing is handled by the Dept. of Consumer Protection, while enforcement is again done by local and state officials.
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In MA the licensing is "The Board of Professional Registration"

In RI as you know, all fire alarm work is inspected and approved by the local fire departments.
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Same in MA along with egress lighting.
 
I dont see why everyone wants to fight mc cable so hard when it is not that much more money for a well protected cable with a no bs ground in it. It doesnt take any longer to put it in only material is a little more.
 
quogueelectric said:
It doesnt take any longer to put it in only material is a little more.
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I hope you don't work as an estimator. ;)

MC cable does take more labor to install than NM. However, it's much faster than raceway methods.
 
quogueelectric said:
I dont see why everyone wants to fight mc cable so hard when it is not that much more money for a well protected cable with a no bs ground in it. It doesnt take any longer to put it in only material is a little more.
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What planet are you from? Tell me you're an employee. For the job I posted about, just using my normal metrics, it would add almost $18,000 to the cost. I'm not fighting MC. I'm cutting costs.
 
mdshunk said:
it would add almost $18,000 to the cost.
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Yeah I can't imagine why you would not just eat that. :grin:

We did a 80,000 sq ft Super Market about 8 years ago where the customer requested MC in place of NM. We had no problem doing that, the change from NM up to MC was about $60,000 on about a $575,000 job.

IMO that is significant and not one that someone is going to do it for no reason.
 
peter d said:
Any particular reason why they made the request for the change?
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Yes, all political.

The customer needed concessions from the town and the Fire Chief had a personal issue with NM in a non-combustible, sprinklered, fire alarmed, single story building with plenty of exits that no one slept in.

It is also the only one of those stores that I have ever seen with spray on fire proofing on all steel.
 
peter d said:
That's why the whole "wire the whole thing like a 'commercial building' " seems like it only comes from those that don't understand the specific code sections in the NEC.
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mmhmm. here's a good one: an electrician here was called to do some work in a metal pre-fabbed building that was a dwelling (had wood framed interior walls, no dropped ceiling, exactly like any other house). They looked at the job and found that it was wired completely in romex. They told the homeowner that the work they needed to do would have to be in 'MC' cable because "its a commercial building" ???. Homeowner calls inspector, inspector calls electrician to say romex is fine. Now the electrician is telling everyone in town that the inspector is an idiot. I tried to correct the electrician, but they wouldn't listen. "any metal building is commercial!"

And I think Marc's proposal for the electrical system is just fine, by the way.
 
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