Other than rewiring the whole thing?
I bought a home like that once, and an electrician recommended we just replace all the outlets with GFCI outlets.
That’s what I did with my folk’s 1940’s house.
Took me around 2 days to do them all.
Here’s the issue: the wiring is almost certainly woven insulation, and it gets extremely brittle with age. When you pull the wires out to install the new outlet, you run the risk of damaging the insulation. It means very careful, and slow going.
Hard to say what you have. The mid-60s was a turning point in home wiring with rapidly increasing use of modern NM (Non-Metallic sheathed cable). That was usually done with 2 wire+ground cable, so potentially that 3rd wire is there and only 2 prong outlets were installed, but that seems unlikely. A very serious potential problem was the use of aluminum wire instead of copper. If that’s the case you should definitely rewire. As a master electrician once told me, there’s a rule about when to use copper and when to use aluminum. The rule is: Use copper.
Or get a bunch of something like this, so you don’t even have to disturb the old wiring.
We rewired our house (previously her house) when I moved in after the wedding. Wasn’t cheap, but we got peace of mind.
I am not an electrician, and I would like someone more knowledgeable to back up my advice…
- Carefully map out every circuit. Every outlet, switch, light fixture, whatever.
- Determine which outlet is the first “stop” on each circuit running from the main breaker.
- Install a GFCI outlet in each of these first stops.
- Replace every other outlet with a standard 3-prong outlet.
As I understand circuits, this will both protect you and allow 3-prong plugs in every outlet. I believe this is your goal.
Again, someone else will come along to agree or disagree.
mmm
Just finishing up rewiring my entire house, and I second this sentiment.
Got lucky with my old house as all the existing wiring to the two prong outlets was armored cable. Metal boxes and conduit completed the run. Only issue was the conduit was not bonded to the breaker panel as that was newish and wires ran through PVC. I redid the run from the last box to the panel and pulled a ground lead for that section. Now I have a ground at every outlet I’ve tested. I’ve been switching to 3 prong as time permits. Very little inside a residence actually runs a third ground wire. Fridge, freezer, AC, computer, some garage tools, fireplace blowers, microwave, maybe the vacuum.
Nothing else off the top of my head. Rest of my electronics, lighting, and kitchen appliances are all two wire. Even most of my space heaters. The commonality seems to be a metal frame as opposed to plastic or ceramic.
We have a house about that old and it took the electrician less than a day to convert the 2 prong outlets to 3. As a stop gap until you get around to it, they sell converters.
https://www.amazon.com/Grounding-Converter-Electrical-Industrial-Appliances/dp/B01IA9UERG
Yes, downstream outlets can be protected either by having a GFCI outlet as the first in line, or by installing a GFCI circuit breaker. But all the 2-prong outlets will need to be replaced by 3-prong outlets, which means messing with very old wiring. That said, if the house is 55 years old, which translates to mid-60s, when better insulation was more common on non-metallic sheathed cable, so it may not be as bad as one may think.
IANAE but my understanding is that those cheater plugs should basically never be used. Even if you connect the ground strap to the box, it is just floating unless the box is grounded. And then if you plug in a three prong plug, you have a potentially dangerous situation where a device that expects a ground is getting power but has no ground.
I hear you but early 60’s I think most building codes required grounded boxes, iirc. I would obviously recommend getting the outlets properly converted.
Scratching my head. If you have 2 prong outlets and wiring behind them with no ground, where do you ground a GFCI outlet?
GFCIs don’t need a ground.
However, a GFCI is not a full substitute for a ground connection. For example, all good surge protectors need a real ground.
So how does a GFCI detect a leak to ground? Does it measure current across the hot and neutral, or possibly a voltage drop below X between hot and neutral?
It measures the balance of current between active and neutral. Out of balance, it assumes the missing current is flowing through you.
I would be unhappy with just relying on a GFCI. A faulty device can be sitting with its case live, and the breaker won’t trip until you touch it. This could be ages after the fault occurs. Not a happy situation.
This is a good point I hadn’t thought of. GFCIs will eventually fail.
mmm
I am an electrician, though the majority of my background is not in household wiring systems.
Personally, I’d establish the existing conditions first, since it’s cheap and easy. I would not be at all surprised if you find that you have metal boxes that are bonded with a grounding wire. You may have any one of a number of different cable types that were popular in the 60s. Just pull a few random outlets apart to check it out. Or, you can take the front off your service box and see what kind of cable was used.
If you do have a grounding conductor at each box, you’re golden. Use compression (not wire nuts) connectors to add short extensions to the grounding conductors and install grounded receptacles. Be sure to check your grounding conductors back to your grounding electrode first to make sure they are continuous.
If you don’t have grounding conductors, replace the breakers for your receptacle circuits with GFCI breakers. (This obviously won’t work if you have plug fuses, so you would need to switch to the plan of replacing the first receptacle in each circuit with a GFCI.) I prefer the GFCI breakers because it seems like the GFCI receptacles either get installed in inaccessible places (e.g., behind the couch) or that they accidentally get tripped when someone touches the “Test” button. This can be very irritating.
Replacing the other receptacles with three-prong receptacles is the same in either case, though I’m always leery of installing a receptacle that appears to be grounded when it is not. This is simply inviting trouble.
I’ve never seen a full wiring job done except during the construction phase. I assume you guys didn’t open walls, that the electrician(s) fished new wire along the paths of the existing wire inside the walls. So I’m curious — how long does it take to do a whole house that way?