Interesting option proposed for unique situation

Thats old cloth NM. I learned on this forum in the state of MA here they outlaw 250.130(C) I am not sure why and some village inspectors dont know or care.

FYI you can still buy new two prongs and use them for replacements. I got some recently for a job where the boxes were to hard to get out of plaster wall. My iphone charger is a 2-prong same with my desk lamp etc. 3-prong is over rated.
 
Joe.B said:
This is a 40's era house that has no EGC's run throughout the house. The main service has a GES that includes a copper water line per 250.52(A)(1) and two ground rods per (A)(5). At some point a previous owner had "upgraded" all the receptacles in the house to 3-prong without supplying any EGC's, and didn't add any GFCI protection.
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I see this kinda thing often in old homes, personally unless its a damp or wet area that would need a GFCI anyway or something that really needs a 'ground' why not just replace a two prong with a two prong?
If you have a computer desk or audio desk pull a new circuit to that and leave the old cloth stuff be, you cause more problems by touching it.
 
pipe_bender said:
I see this kinda thing often in old homes, personally unless its a damp or wet area that would need a GFCI anyway or something that really needs a 'ground' why not just replace a two prong with a two prong?
If you have a computer desk or audio desk pull a new circuit to that and leave the old cloth stuff be, you cause more problems by touching it.
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The problem I see most often is that someone has already replaced the old two-prong with a grounding type receptacle, either without an EGC, or worse, a bootleg ground. That creates a code violation and a hazard. In this case (and most others) if they have to replace the receptacle anyways they will prefer the GFCI over the two prong for convenience.
 
Joe.B said:
The problem I see most often is that someone has already replaced the old two-prong with a grounding type receptacle, either without an EGC, or worse, a bootleg ground. That creates a code violation and a hazard. In this case (and most others) if they have to replace the receptacle anyways they will prefer the GFCI over the two prong for convenience.
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Yeah sorta except one key detail there; a GFCI is like 3x the size of a two prong,
and old buildings here have minuscule metal boxes really plastered in,
I just cant fit a GFCI in those. (actually one time I did and somehow I energized the box so the ground was hot)
And not much stuff needs a 3-prong in living-room or bedroom anyways.
Its all USB-C
In a old kitchen I'd just say rewire it, probably needs two circuits any way and needs to be 12.
I have used wiremold extension boxes to put in a GFI in say a bedroom or bath, they have non metallic extensions.
The way the old metal boxes were designed in my area is they had a C clip that cups the wooden lathe so if I pull the box out the wall (plaster and lathe) starts to come with it. I damaged a few walls before I quit getting those boxes out. You can cut the wall around the box but good luck cutting that plaster then lathe.
Two prongs work great, 3-prong is over rated, I have even put a GFCI up stream of them 2-prongs.
I highly recommend new 2-prongs that keeps the old brittle wire left alone and the outlet gets a fresh look.
For a bedroom appliance load like a window AC or computer / audio desk i'll pull a dedicated circuit and leave old cloth wire dog sleeping.
 
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There comes a point when you can't let the old wire sleep. If it doesn't pass the bend test it comes out IMHO.

I am in the middle of doing a 100 year old house now. You become an expert carpenter and plaster patcher.

The worst problem I have found is ceiling lights originally pull chain so you have 4 old two wire cloth BX cables in the ceiling and the fixture that is supposed to have a max of 2 60w lamps has 2 100s in it and the wires are overheated and disintegrated.

you have a choice with cable fill. Use the old device boxes with usually 1 cable in them and a lot of junction boxes in the basement and attic or rip the boxes out and put larger ones in and daisy chain.

I did some of both.
 
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