Are the outlets actually grounded. Did you remove a cover and look? Three prong outlets are not a guarantee of what you have. Never assume. Just because you see armored cable, does not mean the boxes are metallic. Two wire ungrounded was very common in 1924. Did you find any K&T in the home? It could just be a partial upgrade at the panel from years ago.
I didn’t assume anything with these. The outlets are actually grounded, I verified every outlet. I also opened a number of them and they were consistently lacking ground wires even though they had continuity to ground. There was no evidence of the house ever having had Knob and Tube, no remnants, no holes, etc. Parts of the system have been upgraded to newer NM, but several parts of the house still used the BX or FMC as ground.
It sounds to me as if the City is requiring an upgrade for compliance with current standards, which would mean that ALL branch circuit receptacles be protected by ground-fault circuit interrupters.
Are you saying that proper grounds will need to be run to install the GFIs or will they simply need to install them and mark them as non-grounded? Thanks for the help guys.
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