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Attic wiring - ceiling lighting uses 14/2 cable without ground

Attic wiring - ceiling lighting uses 14/2 cable without ground

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Old 11-28-11, 08:05 PM
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Attic wiring - ceiling lighting uses 14/2 cable without ground

Sort of a follow-up post to post "Fixing multiple attic electrical issues before blowing insulation".

Cliff notes of that post is that my attic electrical wiring needs some work, and that we don't have the money to hire an electrician. I've done a lot of learning, video watching, and more looking in my house. Definitely up for the task.

It looks like the house-flipper told a half truth when he said the entire home's wiring was redone. The panel is new, and new looking romex is ran everywhere in the basement and main floor. It's a 1 story ranch, so that just leaves the attic...

And, they completely ignored the attic. Everything up there is marked "COLUMBIA 14/2 TYPE NM 500". Sadly, it's truly "14/2" with NO ground.

Good news is the wiring in the attic only goes to the ceiling lights. (All ceiling lights are up to 100watt sockets, currently with 13watt CFL bulbs. Not recessed.) I've verified all the outlets are using new-looking romex. They have a ground. Outlets near water have functioning GFCI outlets.


Question 1 - How unsafe is it for light switches & ceiling lights to not have a ground? (Interested in electricution & fire risk.)

Question 2 - Is it against code for light switches & ceiling lights to not have a ground? Or, is there an exemption that allows this for older wiring, since people won't be near these circuits often? (I can hope, right?)

Question 3 - My dad had a thought that I can't see anything wrong with, except that it might not be allowed by code. The cleanest way is obviously to run new romex from the panel, and re-wire everything in the attic. But, since the ground wire is effectively shared among the entire house, could we run a single ground wire up from the attach point on the water pipe to the attic, and have it connect into all the ground leads? I know this isn't the clean way to do it, but is this allowed under code to make old work better? Or is this something that makes you want to cringe for good reason, and say OMG don't do that?

Question 4 - This 14/2 NM cable looks metallic, but it's actually a braided fiber or paper with a silver and shiny finish. Any reason why this type of outside is less safe than the plastic that today's romex uses?


Cost is a big factor, but at the same time, I'm willing to do what I need to do to make the house safe. Taking a shortcut of running a separate ground wire and putting all splices in the attic into junction boxes would save money that we need and time. But, please let me know if there's something really wrong with this that means I really need to just run new romex and re-wire everything.


Question 5 - If I have to run new romex, it would be very difficult to use the existing cable routes. I can't access half the attic wiring on the basement side due to a permanently installed ceiling that looks like a drop ceiling -- but isn't. (Well, it's not permanent in the sense that I can rip it down and put up something else, but that project is further down my to-do list.) Could I figure out how many light circuits I have, run that many 12/2 NM with ground cables from the box into the utility room 10 feet away, then all up together in a wall cavity into the attic, then dispurse from there? (Dropping down from above to hit the light switches.) I think the worst case scenario is adding 20 feet to one or two of the circuits. Right now, I think the cables go up near their light switch, then to the ceiling light. I'm not sure if this distance matters in the end. And, I'm not sure if it's unsafe to run so many cables and circuits right next to each other.

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  #2  
Old 11-28-11, 08:24 PM
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Question 1 - How unsafe is it for light switches & ceiling lights to not have a ground? (Interested in electricution & fire risk.)
Marginally unsafe. As long as no wires come into contact with the metal parts of the housings the hazard is minimal.

Question 2 - Is it against code for light switches & ceiling lights to not have a ground?
Yes, at least current code. Existing systems that were code-compliant when installed are grandfathered until modified at which time they must be brought up to current code.

Question 3 - My dad had a thought that I can't see anything wrong with, except that it might not be allowed by code. The cleanest way is obviously to run new romex from the panel, and re-wire everything in the attic. But, since the ground wire is effectively shared among the entire house, could we run a single ground wire up from the attach point on the water pipe to the attic, and have it connect into all the ground leads? I know this isn't the clean way to do it, but is this allowed under code to make old work better? Or is this something that makes you want to cringe for good reason, and say OMG don't do that?
This used to be allowed, I don't know if it is still but I don't think so.

Question 4 - This 14/2 NM cable looks metallic, but it's actually a braided fiber or paper with a silver and shiny finish. Any reason why this type of outside is less safe than the plastic that today's romex uses?
No, it is okay as long as the outer jacket isn't severely damaged. Slight damage that does not affect the inner conductors may be repaired with plastic tape.

Question 5 - If I have to run new romex, it would be very difficult to use the existing cable routes. I can't access half the attic wiring on the basement side due to a permanently installed ceiling that looks like a drop ceiling -- but isn't. (Well, it's not permanent in the sense that I can rip it down and put up something else, but that project is further down my to-do list.) Could I figure out how many light circuits I have, run that many 12/2 NM with ground cables from the box into the utility room 10 feet away, then all up together in a wall cavity into the attic, then dispurse from there?
Yes, that is an acceptable practice. You do have to be careful of "bundling" the cables together as that will then involve a derating formula. Generally lighting only circuits can be run with #14 conductors so if you ran #12 (12-2 type NM-B cable) but connected these to 15 ampere circuit breakers you could probably eliminate the problems of derating.
 
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Old 11-29-11, 01:27 AM
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Furd, thanks so much for your responses to all my questions! A few follow-ups, if you don't mind. Going out of my mind here!

NEC 250.130(C) discusses "Nongrounding Receptacle Replacement or Branch Circuit Extensions", which I think covers adding a grounding system to a nongrounded system... Although it's my first look at NEC, and I haven't gotten my head around the section quite yet, but found a few other people referencing it.


Follow-up Question 1 - If you found NM cable without ground was used in your attic for the ceiling lights and light switches only, and the $250 or so for a spool of new 12/2 with ground romex was a lot of money to you, would you leave it be or replace it? {The more I'm looking into it, the less of a problem I'm thinking it is.}

Follow-up Question 2 - If deciding not to install new romex, is the idea of setting up a new grounding wire system worthwhile doing, or do you think the benefit is minimal and not worth perusing? I'm figuring doing such a system would bring attention to the issue to people in the future. Even if NEC 250.130(C) allows it, a future city inspector could have an issue with it, or a future home inspector could recommend to the buyer that there was a problem with it. (Gosh, I just realized I'm trying to figure out if I should leave something less safe to pass future hypothetical inspections better, that's sad.) {The more I think about it, I'm thinking that if I was going to run grounding wire, I should just go the extra step and run the romex.}

Follow-up Question 3 - I've been reading about grounding vs. bonding and how the term grounding is often used where bonding should be used instead. I'm seeing the earth doesn't conduct less than 600V well, so if I were to go with a new separate ground wire, should that be attached to the neutral at the panel instead of the water pipe grounding? {I'm guessing there's a wire somewhere attaching the two, so it might not matter, but I'm definitely not sure about that.}

Thank you so much, again!
 
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Old 11-29-11, 03:51 AM
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Furd's asleep, but until he answers, my take on your situation is leave it alone. Lighting in some instances was done with porcelain fixtures. Not sure how yours is done. With porcelain fixtures, there is no ground attachment point, so it would be a moot point. Since it is in an attic, and not used all that much, I would concentrate on other areas and leave it. As Furd said, once you start messing with it, all of it has to come out and be replaced, which can be expensive, as you have already seen, in just cable cost.
Don't wrap your head too tightly around the NEC, as there are modifications, exceptions and cross references, that can take you to the next millennium to understand.
I'm not saying leave it unsafe, but from what you are saying it operates fully and the cabling is no compromised.
 
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Old 11-29-11, 10:23 AM
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I was awake at the time of posting but I had shut down the computer for the night.

Follow-up Question 1 - If you found NM cable without ground was used in your attic for the ceiling lights and light switches only, and the $250 or so for a spool of new 12/2 with ground romex was a lot of money to you, would you leave it be or replace it? {The more I'm looking into it, the less of a problem I'm thinking it is.}
Leave it. I might consider re-wiring at some future date although most likely I would use 14-2 on a 15 ampere circuit breaker. One thing that you DO need to be concerned about is that the older wire/cable has insulation rated for only 60 degrees C. and if you were to change out any of the lighting fixtures you would need to be certain that you did not use models that require 90 degree C. insulation.


Follow-up Question 2 - If deciding not to install new romex, is the idea of setting up a new grounding wire system worthwhile doing, or do you think the benefit is minimal and not worth perusing? I'm figuring doing such a system would bring attention to the issue to people in the future. Even if NEC 250.130(C) allows it, a future city inspector could have an issue with it, or a future home inspector could recommend to the buyer that there was a problem with it. (Gosh, I just realized I'm trying to figure out if I should leave something less safe to pass future hypothetical inspections better, that's sad.) {The more I think about it, I'm thinking that if I was going to run grounding wire, I should just go the extra step and run the romex.}
Rather than try to run a new/separate equipment grounding conductor, all new cable (type NM-B) would be my preference.

Follow-up Question 3 - I've been reading about grounding vs. bonding and how the term grounding is often used where bonding should be used instead. I'm seeing the earth doesn't conduct less than 600V well, so if I were to go with a new separate ground wire, should that be attached to the neutral at the panel instead of the water pipe grounding? {I'm guessing there's a wire somewhere attaching the two, so it might not matter, but I'm definitely not sure about that.}
I congratulate you on reading a subject that is at best difficult to understand even for people that work with this every day. The "neutral-ground bond" takes place at only ONE point and that is the SERVICE panel. A service panel is the first means of disconnect after the electric meter. For most single-family homes this is the only panel but sometimes there may be a disconnect switch between the panel and the meter.

Since you are reading about grounding vs. bonding you now know the sole purpose of the equipment grounding conductor is to provide "a low impedance (low resistance) path back to the source (of electricity) to facilitate the operation of the overcurrent device (fuse or circuit breaker) cutting off power to the circuit." As such the equipment grounding conductor MUST go to the equipment grounding bus in the panel supplying the circuit. In a service panel this will always be the same as the neutral bus but if you have a "sub-panel" then the neutral bus will be isolated from the equipment grounding bus.

Confused yet?
 
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Old 11-29-11, 07:04 PM
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Just to throw in another opinion, as long as the wire is in good condition, I'd leave it as-is. Ceiling fixtures in bedrooms aren't pulling that much electricity and the wiring is appropriately sized.

Code-wise it's likely grandfathered in. You can't extend it, so if you do other renovations, you'll want to run new cabling from the panel.

I'm sure you can find other projects to use your money and time.

Good luck!
 
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