How to easily upgrade 2-prong electrical outlets to 3-prong outlets without grounding them

Originally published at: How to easily upgrade 2-prong electrical outlets to 3-prong outlets without grounding them | Boing Boing


My parents house is over 100 years old and has no grounded outlets upstairs, so several GFCI outlets were put in long ago. It works (I had my laptop plugged in to one this weekend), but it isn’t grounded and should be avoided when possible.



Yes, as long as you screw the center screw on the receptacle through the ring on the cheater.


That is unsafe as can be, unless the ring tab is connected to an actual ground - and no, heating/water/gas pipes are NOT a ground.

In case of a fault where live and ground (quite probably the external shell of the device) get connected, some degree of electrocution is almost assured in the absence of a GFCI/RCD or whatever it’s called in your locale (‘differenziale’ in Italian, JFB - Jordfelsbrytare in Swedish).


Grounded outlets in dry rooms are one of those things that might save perhaps 10 lives a year in the USA, any more. Most portable electrical equipment is now made with plastic cases instead of metal cases. There are a few exceptions, such as fans. So an ungrounded outlet is rather low on my list of things that could kill me. Also, things that plug into the bathroom are now required to have little GFCI circuits in their power plugs.
That said, you can protect the entire string of outlets on a single circuit breaker by installing a GFCI in the first outlet in the string, then using its output terminals to power the rest of the string. This is assuming that you can see where the wires between the outlets are routed in the crawlspace. I used this trick when I bought a 1940s house with all 2 prong outlets on four different circuits.


I am not an electrician, but I have been an electrician’s flunky. So take this for what it’s worth. Also, if you’re a renter, well, good luck with the landlord.

If you know where/how the wiring for the outlet gets back to the breaker box, it might be worth considering just rewiring and maybe even putting in a new breaker. I’m saying this because it’s likely the breaker and wiring is old if you’re looking at an ungrounded outlet. And if the wiring is easy to run – whether it’s following the old wire or taking a new easier route – the added safety might be worth it. The cost to you would be mostly related to running the new wiring, because the outlet itself and the breaker are 5-10 minutes each. (I’m assuming you’re hiring a licensed, bonded, house-broken electrician.)

Also, there are shoddy GFCI outlets running around. Don’t just buy one off Crazy Eddy on Amazon/ebay/whatever.


I have to ask here, why?
I imagine the screw is connected to the internal metallic frame of the receptacle, but in an ungrounded one, how’s that supposed to be of any help?


Not quite. Electrocution isn’t assured unless there’s a sufficient electrical connection between the other end of the human and the ground, i.e. the floor or a water pipe etc. Touching a ‘hot’ lead isn’t a problem in itself, it’s when you complete a circuit that lets the current flow through your torso, like standing on a wet concrete floor in bare feet when touching said ‘hot’ lead.
It’s still something to avoid on most days.


Yeah. The sensation varies from tingly/weird to ohfuckthathurt.

Or, I guess, dead. Can’t speak to that one.


but it should be labeled with a “No Equipment Ground” sticker.

where’s a good source for a “Totally F’ed-up - Don’t Use” sticker?


And if you’re doing that grunt work anyway, I’d strongly recommend considering adding some low voltage DC line alongside it. Notice how most things you plug in have a power supply to step 120VAC down to low voltage DC? That’s some waste and inefficiency there, and I’m not talking about the wall wart. You don’t even have to connect it to anything yet, just service loop it behind the wall plate and near the breaker panel, then reap the benefits in a year or three. Future proof your shit, yo.


Uggh… the oversimplification in the write-up is going to cost anyone who follows it far more than it ought to.

Firstly, the current NEC code version in the US calls for combination GFCI/AFCI outlets in most locations. Check with your local municipality to determine which NEC version they are operating under, and then still choose combination GFCI/AFCI protection instead of just GFCI. Code won’t penalize you for being extra protective, but it can for being underprotective. For simplicity, I’m mostly going to refer to any of these as GFCI, but understand that your best and safest choice is the combination version.

Secondly, if you visualize the circuit in your home which you wish to convert to ungrounded three prong, the GFCI outlet should either go in the first practical position downstream from the circuit breaker itself, or if the breaker box is located in an accessible area (for resets in case of tripping) it would be better just to install a combo GFCI/AFCI breaker where the old breaker was. Once that GFCI breaker or outlet is in place, all remaining downstream outlets in the circuit can/should be normal three-prong outlets (but MUST be identified on their face with one of the “GFCI-protected ungrounded outlet” blue stickers that came in the box with the GFCI outlet).

So… a simplified flow diagram would look thusly:

Breaker (GFCI/AFCI) > 3-prong labelled outlet > 3-prong labelled outlet > 3-prong labelled outlet (…) > 3-prong labelled outlet


Breaker (normal) > GFCI/AFCI combo outlet > 3-prong labelled outlet > 3-prong labelled outlet > 3-prong labelled outlet (…) > 3-prong labelled outlet


  1. GFCI/AFCI outlets always provide downstream protection if they’re wired correctly

  2. the downstream protected outlets must each be labelled with one of the blue labels provided

  3. NEVER bridge the ground wire with the neutral wire. That does not afford you grounding safety. If there is no ground wire present for the circuit and the circuit cannot easily be re-run as grounded, then your next best bet is to use the GFCI/AFCI method described above. It’s not magical, but it’s much safer than nothing and it’s code legal and won’t invalidate your homeowners insurance in the event of electrical or fire damage. Bridging neutral to ground at an outlet is not code legal and can cause great harm.

  4. NEVER use the cheater 2 to 3 plug adapters. Screwing them to the outlet cover screw won’t make a damn bit of difference unless there’s an uninterrupted conductive path from the outlet body to the workbox to the conduit/armor around the wires to the circuit panel to the ground rod. In the event that you don’t have a ground wire in the outlet workbox already, it’s effectively certain that you don’t have a useful ground path back to actual ground. Even in the edge case of a mid-century electrical conversion where BX was run throughout (not typical in residential, but definitely did happen now and then and is grandfathered in NEC), the BX flex jacket is likely going to offer an elevated impedance path to ground and thus shouldn’t be relied on strictly on its own.


I’d learned back in the day that cold water lines were an acceptable ground. Of course, the person I learned that from was known for his catchphrase of “That’ll work, until it don’t.”


I’d learned back in the day that cold water lines were an acceptable ground.

Many years ago the attitude was more cavalier towards this kind of dangers.
That said, using water pipes for ground has always been bad advice for two main reasons:

  • It could kill your neighbor, if they touch a faucet and you have a ground fault (Ok, this might be seen as a plus in some cases)
  • There can easily be (especially in modern houses) joints or sections of non metallic piping, making it completely uneffective.

As driving without belts is not a problem in itself.


The comments are interesting.

I have never once looked at an electrical circuit of any kind and thought to myself, ‘ah, good, they went with electrical tape, I’m dealing with a real pro here.’

I’m not sure if this can be stressed how HORRIBLE of an idea it is to DIY electricity. Grounded outlets, even if labeled as not-really, are not a safe bet, even if just grounded to a metal box. GFCI is the absolute minimum, but really isn’t a good idea if you don’t know what you are doing.

Please stop publishing articles about how to DIY electrical issues. The last thing anyone without a state issued electrical license should be doing is electrical work. I didn’t see any references to Electrical Code in this article. Which is what governs electrical installations.

etc etc.


This. My “new” house is a little under 100 years old and has all the old “knob and tube” wiring. We’re in the process now of having all the electrical replaced and brought up to current codes. Now that I see the walls off and the wiring exposed, I don’t know how the house didn’t burn down long ago.


I find refreshing that a fair dose of good sense is shown.
They all are very mild and civil too, in another of my go-to forums both the OP and some advice here would have been thoroughly roasted.


Hell, I have that same thought with modern Romex and drywall.