Why hasn't this burned down?

[Fred B]

I have an older home that am working on circa 1970, been atleast one newer rework but still with the older wiring, all older NM 60^o C. Question, why hasn't it burned down? Found multiple sliced conductors both hot and neutrals. In the j boxes, panels, and receptacles. Haven't opened them all as scope of job it wasn't called for.
Slices just like this.


Another question, could those slices have opened over time and not noticable on initial installation where wire was only scored then opened as they aged? Looks like whomever did installation while removing NM sheath with a blade cut into the conductors.
Also found evidence of heating on the breakers. And found one receptacle that had been arcing and found weld mark on terminal screw and the sliced wire in that box. Wire actually broken in 2 at arc point and being held together with electrical tape, and was still "working".(Was working on that line when found it). Have recommended rewire but owner is unwilling, so how dangerous of a situation is this? Or am I being over cautious? And what is my level of liability for not doing a complete rewire, as I've already done some work before finding all these issues? Would doing a full megger be advisable as it would definitely show the damaged insulation? Or is there another way to test proof of wire condition to convince owner to do the rewire? Not hungry for the work but more concerned about covering my butt.

 

[Dennis Alwon]

Looks like bad control of the nm stripper... He/she probably used the style of nm stripper shown below

 

[James L]

It's dangerous in that you have both hot and neutral wires split open. May not be really close to each and posing arcing problems in the panel or anywhere else you can see right off.

I'm with Dennis. This was more than likely a really bad stripping job when new. And my guess is it's not just the panel. Probably all over the house on the switches, receptacles and lights. I've seen it like that.

If they don't care, best you can do is write a diagnosis/warning on an estimate form and leave it with them.

 

[ActionDave]

I have an older home that am working on circa 1970, been atleast one newer rework but still with the older wiring, all older NM 60^o C. Question, why hasn't it burned down? Found multiple sliced conductors both hot and neutrals. In the j boxes, panels, and receptacles. Haven't opened them all as scope of job it wasn't called for.
Slices just like this.

I would say the general reason it hasn't burned down because electricity rarely causes fires. A more specific reason would be that even though the picture indicates some damaged insulation there is nothing there to cause a fire.

Another question, could those slices have opened over time and not noticable on initial installation where wire was only scored then opened as they aged? Looks like whomever did installation while removing NM sheath with a blade cut into the conductors.

It's a bad stripping job of some old romex. I didn't ever run my knife down the length of a piece of romex. I always made cross cut perpendicular to the conductors on the sheathing where the cable entered the box

Also found evidence of heating on the breakers.

No clue what this means

And found one receptacle that had been arcing and found weld mark on terminal screw and the sliced wire in that box. Wire actually broken in 2 at arc point and being held together with electrical tape, and was still "working".(Was working on that line when found it).

You found something wrong in a junction box. Fix it and move on. That's why we like splices and connections inside junction boxes.

Have recommended rewire but owner is unwilling, so how dangerous of a situation is this? Or am I being over cautious?

I agree 100% of the time that an upgrade is the first choice when it comes to old wiring, but hey, ya know I gotta admit I've run my tires a lot longer than the penny in the tread rule said I should. Tell them what's up and the rest is on them.

And what is my level of liability for not doing a complete rewire, as I've already done some work before finding all these issues?

Don't know. Lots of work gets done everyday on buildings and cars. Do you think you could get away with suing your mechanic for a blown head gasket after he changed your u-joints?

Would doing a full megger be advisable as it would definitely show the damaged insulation?

You've got insulated conductors wrapped in insulating sheathing, separated by physical space inside the sheathing, stapled to a non conductive surface. Is a full megger test really going to find damaged insulation or is it going to find that one thing you forgot to disconnect before you hit the button?

Or is there another way to test proof of wire condition to convince owner to do the rewire? Not hungry for the work but more concerned about covering my butt.

You told him the thing to do is a rewire. He refused. When did your butt get uncovered? Wait......don't answer that.

 

[__dan]

Question, why hasn't it burned down?

where wire was only scored then opened as they aged?

Also found evidence of heating on the breakers

And found one receptacle that had been arcing and found weld mark on terminal screw

and being held together with electrical tape, and was still "working".

The wiring that's in a box, the heating and smoldering is very localized and the materials are mostly non combustible. Those problems contained in a box, the 99% of failures will be it just stops working and the 1% would be all other troubles, including fires, shorts, blown fuse. That's in residentail stuff. Large commercial or industrial stuff could just keep burning down until the power is cut.

Discoloration of the copper by heating is something I am always looking for and sure sign that the device is EOL.

If the problem esists outside the box, cable passes through wood framing or stapled to it with staple through the cable, hard bend in SUE smoldering at the 90 through the joist header, squirrels chewing on wire in the attic (heard that one a few times), that's a fire hazard.

Your liability for the existing, you have a duty to mitigate damages, but it's not your property so you cannot touch it without the owner's permission (or his agent). I would feel obligated to note deficiencies in writing, and my liability would extend to, I could see the owner saying 'hey I did the right thing by hiring a licensed guy' (you would be obligated to show that you excuted on your duty to mitigate damages, by having the email, pdf, you sent advising him of this condition and possibly recommending additional spending to continue looking at the problem ...).

You would also have to discover how the owner wants to move foward, based on the additional information you discovered and conveyed to him.

 

[Fred B]

The wiring that's in a box, the heating and smoldering is very localized and the materials are mostly non combustible. Those problems contained in a box, the 99% of failures will be it just stops working and the 1% would be all other troubles, including fires, shorts, blown fuse. That's in residentail stuff. Large commercial or industrial stuff could just keep burning down until the power is cut.

I've had one in residential, I was there when the guys were cutting with a sawzsall to remove some wall members and they cut into a wire for an electric heater. It started sparking and burning running right up the wire until we got to the panel to shut it off. Breaker never tripped.

Discoloration of the copper by heating is something I am always looking for and sure sign that the device is EOL.
If the problem esists outside the box, cable passes through wood framing or stapled to it with staple through the cable, hard bend in SUE smoldering at the 90 through the joist header, squirrels chewing on wire in the attic (heard that one a few times), that's a fire hazard.
Your liability for the existing, you have a duty to mitigate damages, but it's not your property so you cannot touch it without the owner's permission (or his agent). I would feel obligated to note deficiencies in writing, and my liability would extend to, I could see the owner saying 'hey I did the right thing by hiring a licensed guy' (you would be obligated to show that you excuted on your duty to mitigate damages, by having the email, pdf, you sent advising him of this condition and possibly recommending additional spending to continue looking at the problem ...).

You would also have to discover how the owner wants to move foward, based on the additional information you discovered and conveyed to him.

I've repeatedly kept them updated to what I was finding and response has been "we'll be doing a rewire in phase 2 of the construction". That appears to be a couple of years from now. If it happens. They plan to move into house sometime this month.
Now a letter with advising of issues found and remediation suggested is fine but if they sell in mean time I know 99% of time disclosure doesn't happen. If it was a heating system they have the right to "red tag" the furnace. It seems there should be something similar in place to address inherently unsafe electrical. Although this may not qualify, as even though finding multiple issues it hadn't burned in over 40 yrs.

 

[__dan]

Once they know of the problem, you're in the clear and it's all about how much they want to spend on what, now. They either do or don't want to spend money on it now.

You just have to have that document, pdf, email, the years later when it gets called out again, when of course you are getting some of the blame (now it's a problem), and you just send them of copy of that saying 'yes I was aware of problem and conveyed that finding to you'.

if you have to wonder about why they have so much crap work, it was probably the not spending money that got them there. That and thinking hack work is cheap.

 

[ramsy]

..99% of time disclosure doesn't happen. ..there should be (the right to "red tag") inherently unsafe electrical.

Inspectors can "red tag" per NEC 110.12(B). Is this job being inspected?

 

[Fred B]

Inspectors can "red tag" per NEC 110.12(B). Is this job being inspected?

Yes

 

[WasGSOHM]

Question, why hasn't it burned down?

Somehow over decades the HO did not pull enough amps out of his wiring for long enough? That HO is incredibly lucky.
Didn't he see flickering lights?

 

[Fred B]

Somehow over decades the HO did not pull enough amps out of his wiring for long enough? That HO is incredibly lucky.
Didn't he see flickering lights?

Don't know the original owner is not the current owner they just bought it so no history. That's why was just there to disconnect some wire for some wall removals, change some lights, and found the mess.

 

[romex jockey]

good lord, first day for some apprentice who forgot his glasses there ....?

~RJ~

 

[WasGSOHM]

Maybe bad connections can heal themselves by being welded closed by the heat, like relay contacts sometimes weld?

One time out of 100?

 

[gadfly56]

Looks like bad control of the nm stripper... He/she probably used the style of nm stripper shown below

I've never used that, but I have done only a handful of connections ever. How do folks here usually strip the NM to make connections? The few times I did it, I was very aware of how green at it I was. I would slit the last 2 inches lengthwise then peel the outer sheath down about 6 inches, like a banana. I'd cut off the last 2 inches of conductor, trim off the peeled sheath and then strip the conductors and make up the connection.

 

[WasGSOHM]

Nicking the conductor concentrates stress and creates a weak point, just like nicking a piece of glass?

 

[James L]

I've never used that, but I have done only a handful of connections ever. How do folks here usually strip the NM to make connections? The few times I did it, I was very aware of how green at it I was. I would slit the last 2 inches lengthwise then peel the outer sheath down about 6 inches, like a banana. I'd cut off the last 2 inches of conductor, trim off the peeled sheath and then strip the conductors and make up the connection.

I use my t-strippers.

At the smallest hole, near the nose, squeeze gently enough to just touch the sheathing. Then push forward and rake the teeth across the sheathing.

Then just pull the sheathing off.

Note - there's a big difference between gentle and slow. I have found the slower and more careful you consciously tried to be, the greater the likelihood you squeeze too hard and Nick the insulation on the conductors.

Gently, but smoothly and quickly

 

[Dennis Alwon]

I use the ideal tool. It will strip 12/2 and 14/2 and if you are careful you can also strip 14/3

 

[hbiss]

I've never used that, but I have done only a handful of connections ever. How do folks here usually strip the NM to make connections? The few times I did it, I was very aware of how green at it I was. I would slit the last 2 inches lengthwise then peel the outer sheath down about 6 inches, like a banana. I'd cut off the last 2 inches of conductor, trim off the peeled sheath and then strip the conductors and make up the connection.

I've used that tool for almost all of my career, even on round 3 wire. Never damaged a conductor. I think the problem is poorly trained "ropers" being made to push out work as fast as possible.

I think you could do even more damage with a razor knife or a hawk bill knife which many like to use.

-Hal

 

[Rock86]

I use the ideal tool. It will strip 12/2 and 14/2 and if you are careful you can also strip 14/3

I've used this... the Klein version... I found it either didn't cut the jacket all the way or it would nick the insulation on the conductors. It wasn't worth playing roulette for me. But that is just my experience.

 

[Dennis Alwon]

I've used this... the Klein version... I found it either didn't cut the jacket all the way or it would nick the insulation on the conductors. It wasn't worth playing roulette for me. But that is just my experience.

Never had an issue with it. Maybe the Kleins version have a problem.