DU feeders

[barone]

Can a dwelling unit feeder in a multifamily high-rise, be physically run through another dwelling unit?

The feeder originates in a meter center, is connected to a main breaker (2Pole-100A), runs through several other dwelling units and terminates in a load-center in the dwelling unit it serves. The feeder is 100A-120/208V-1PH-3W and wiring method is MC cable run concealed behind a sheetrock ceiling/wall.

I can not find anything in the NEC prohibiting this, but it has been turned down by inspectors in the past, and my gut tells me it is not a good idea.

Any input would be greatly appreciated.

 

[celtic]

Can a dwelling unit feeder in a multifamily high-rise, be physically run through another dwelling unit?



I can not find anything in the NEC prohibiting this, but it has been turned down by inspectors in the past, and my gut tells me it is not a good idea.

Any input would be greatly appreciated.

What do they with the plumbing supply and DWV lines?
Exhaust fan venting?
Line sets for AC?
LV applications such as phone, cable, FA?


It is kind of unreasonable to require all these different systems - that sometimes interconnect - to run w/o infringing on another units air space.

Must be a real torturous task to plumb a tub w/o the trap in the downstairs neighbors ceiling space :roll:


Have the building dept. provide you written documentation of their policy/standard.

 

[barone]

Celtic,

First off I like the Handle. Secondly, I suppose I should have been clearer. These are run horizontally, and instead of routing them above the corridor ceilings and then into each unit, all the units on one half of the building are run thought the units on that half of the building. So the unit closest to the electric closet has 6 or 7 feeders running through it, then they drop off as you move away from the closet. The second to last haveing two feeder though it.

I do agree that other systems (plumbing, HVAC, etc.) run through dwelling units they do not supply, especially vertical runs, but those are not electrical, so I really do not care to comment on them. Also, when those system run through those units, depending on the system, they are sometimes provided with a fire rated enclosure and these feeders are not. Those systems typically are not metered individually, so there is no incentive for a tenant to cut into them to steal services.

I guess my biggest beef is that the conductors can be tapped. I know they are MC but with the high cost of electrical service these days I've have seen some crazy things done to steal electric. And I assure you given the time and tools, MC cable can be broken open and tapped. My second concern would be when the person who owns or rents dwelling unit one (with the six feeders passing) decides he wants to renovate his condo or rental and he tears into the walls and ceiling, he may be directly handling the service feeders of those other units, and performing demo operations (which are not usually done with the greatest of care) may cause damage to the cables. I know that one is a reach, but stranger things have happened. If the wiring method were pipe and wire or bus duct, or some other well protected means I would let it go, but its MC.

So I still have the same question. Am I missing something in the NEC or is there another building code that prohibits this install? If not great, but if so it would help my argument for the building owner to have those feeds run down the corridors. If it were my building I would want to be able to get to those feeders in the future without having to put out another tenant, or better yet shutting down half the units on the floor to work in unit one.

Thank for your input.

 

[Jljohnson]

In the area that I work in, the "general" rule is ... if it is a rental unit it is OK but if it is a "for sale" unit (condo style) then the feeder has to be kept out of the adjacent units. Mind you, this is NOT an NEC requirement, just local AHJ requirements. FWIW, in one neighboring town, the "official" position is as outlined above but with one friendly phone call I have successfully gotten the requirement waived, the only thing I had to do was make sure that the feeders were concealed behind drywall. In some cases, we have run the feeders in the slab and turned them up into the wall at the panel location. This scenario still leaves you piping a 2nd, 3rd, etc. floor through the units below them but it is concealed in a wall cavity and in conduit.

Best advice is to call the local buildig department and/or utility provider and ask what their requirement is.

 

[barone]

Thank you very much for your responses fellas. You both seem to agree that a call to the building dept. is a good idea. It is kind of a high profile job so I think it is probably better to just write a letter stating that I disagree with the install and call it a day. Both of you gave me very good input and it is greatly appreciated.

 

[barone]

On a side note Jljohnson, we have had several buildings that were built as rentals, eventually go condo, and then we get sued by the condo associations for something we did not have anything to do with (plumbing issue, or structural problem, etc...). I get the feeling in a few years the same may be true here. Once the market returns this building will probably be worth a lot of money. It is a green building in a major Metropolitian center.

So if I just let it go, because it is currently a rental, in a few years when it goes condo and someone demos their condo, we'll no doubt be sued. Even though we did not install it. We are just the silly electrical engineers/designers, and we get sued because we have professional insurance, not because be do faulty designs.