Background: I recently moved into an apartment building in Canada (built in 1969). I don't know much about the electrical code, how grand-fathering works within it, etc., but I have an intermediate knowledge of household wiring.

Some previous electrical shenanigans raised my suspicions and induced me to do some investigation in my new apartment's electrical work.

My first observation: none of my receptacles' junction boxes have grounding wires going into them. I figure that's a byproduct of the age of this building. My circuit tester doesn't complain about an open ground. I've read that electrical cable conduit could be used to provide grounding, so I figure that must be what's going on. Is this correct?

Second observation: None of the receptacles' junction boxes have grounding screw terminals. Instead, a knockout cover was punched out on one side, and used to improvise a clamp that holds down a short ground wire.

Wire barely held in place by the clamping force of the knockout cover

Seeing that made my jaw drop. There's barely no mechanical retention here. I was able to pull that cable loose with practically no tension at all.

So my questions:

  1. There's no way that's legit, right?
  2. Is is possible that the building is grand-fathered onto old electrical code rules, and doesn't need to provide proper grounding?
  • Can you post a photo that looks up into where the wires enter the box from? Nov 5, 2019 at 2:33
  • @ThreePhaseEel They come in from a regular metal conduit on the right side. Here are some more camera angles: imgur.com/a/eHYC4Hy
    – Alexander
    Nov 5, 2019 at 3:25
  • Do you own this apartment, or just renting? Nov 5, 2019 at 7:47
  • @Harper Just renting. This is the state of the system after my first maintenance request. I'm going to make a second, but I want to be much more precise in my request, to make sure this gets fixed. I just wanted to be sure I wasn't wrong in my assessment that this is jank.
    – Alexander
    Nov 5, 2019 at 13:45
  • 1
    I don't know what to tell you about carnal knowledge. Your best bet is probably to contrive a story about being shocked by touching the case of your PC, then ask the landlord to deal with it, or get permission to have your electrician go through the place and make sure all the grounds are right, and then do exactly that. Nov 5, 2019 at 15:45

2 Answers 2


The conduit's fine...but that ground wire sure isn't

While a properly installed conduit system provides quite solid grounding performance, the pigtail from the receptacle isn't what I'd call an acceptable level of workmanship by any stretch of the imagination. I would get a proper 10-32 grounding screw and use it to attach the pigtail to the ground hole in the back of the box if I were in your shoes.

  • Interestingly, I don't see any screw holes where a grounding wire would go. Probably because the junction box is so full of dust, drywall, plaster and shit. Maintenance will take care of it now (I hope).
    – Alexander
    Nov 7, 2019 at 21:51
  • @Alexander -- if there's no screw hole, it should be possible to use a 10-32 (the pitch is important!) self-tapping/self-drilling screw from the inside of the box, still, or maybe get a ground clip slid onto the edge of the box Nov 8, 2019 at 0:39
  • I'll let the apt maintenance take care of it for me. (Whether or not they're actually competent enough... tbd) but I'm curious, why is the thread pitch important?
    – Alexander
    Nov 8, 2019 at 1:02
  • @Alexander -- you need enough threads biting into the metal to provide both sufficient mechanical holding and sufficient electrical continuity between the screw and the box, and a regular sheet metal screw won't give you that Nov 8, 2019 at 1:04
  • 1
    Update to the story: So as it turns out, the ground wire wasn't pinched in place the way I thought it was. I thought it was that way given the appearance of the wire and the way the punch-out cover looked (folded out on one side). What they actually did was wrap the ground wire around the 6-32 machine screw that holds the receptacle to the junction box. That came undone when I took out the screw, which left it hanging (and pointing out the very clear flaw with that approach).
    – Alexander
    Nov 14, 2019 at 17:57

Use higher quality "spec grade" receptacles marked "Self-Grounding". They will automatically pick up ground from the steel box via their mounting screws. Switches will also do this even if not marked.

However, the boxes appear to be inset more than 1/4” into the wall. Because this is a non-flammable wall material (plaster or drywall) up to 1/4” (6mm) is allowed. This is too much. Extension sleeves will be needed to provide adequate enclosure.

  • I'm moved out of this apartment (we got our own house! 🥳), but looking at other outlets at a later time, I think what they did was wrap the ground around 1 of the 2 machine screws holding the receptacle to the box. Super sketchy!
    – Alexander
    Dec 16, 2022 at 1:18

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