Old house, 2 prong outlets - safety question for kids

Question

I just bought a 1955 house with 95% of the outlets 2 prong ungrounded. There seems to be one grounded 3 prong outlet in each room.

I reached out to my electrician for a quote to add grounds to all outlets in the house. He said I could do that or it would be cheaper to just replace the outlets with GFCI.

I can easily change out outlets for GFCI's myself. But I have 4 and 7 year old kids. What would be the safest or recommended action to take? Have an ungrounded GFCI or grounded regular 3 prong outlets?

Answer 1

The National Electrical Code specifically allows ungrounded 2-prong outlets to be replaced with GFCI outlets or 3-prong outlets protected by upstream GFCI outlets or breakers.

This can actually be safer than a properly grounded 3-prong non-GFCI. For example, if a child pushes a butter knife into the hot prong of a normal outlet, they can be shocked, while a GFCI will prevent any shock. A GFCI functions by comparing the current flow between the hot and the neutral wires. If the difference is more than a few milliamperes, it is assumed the the difference is leaking to ground, maybe through a person, and the GFCI trips.

Obviously, grounded and GFCI is best but GFCI alone is still good.

The only special requirements is that the GFCI outlet be marked “Not grounded” and any downstream outlet be marked “Not grounded, GFCI protected”.

BTW, for a downstream outlet to be protected, it must be powered from the LOAD terminals of the GFCI.

Answer 2

I also have a 1950s house with (until recently) most receptacles ungrounded. However, you may be pleasantly surprised, as I have been, to find good grounds available, despite currently having ungrounded receptacles. To summarize a little of everything, and add a few more things:

• Ungrounded (2 prong) receptacles can often be replaced with grounded receptacles if there is a good ground (ground wire or, less frequently, metal conduit). This provides the default level of protection for most rooms except bathrooms, kitchens, laundry room, unfinished basement, garage
• GFCI receptacles or GFCI breakers plus 3-prong receptacles can be used to provide equivalent protection to grounded receptacles if ground is not available. This is actually superior protection in certain respects, but does come at a cost as GFCI receptacles are more expensive than regular receptacles and GFCI breakers generally more expensive than GFCI receptacles. If you have an older panel then GFCI breakers may not even be an option.
• Any 3-prong receptacles protected by GFCI that do not have an actual ground must be labeled "GFCI protected, no ground" (or similar language.
• Tamper Resistant receptacles are required in most areas now and are definitely a good idea with little kids.
• What you must not do is to bootleg ground to neutral. That will fool a 3-light tester but not provide any safety, and in fact be less safe that a 2-prong receptacle because it would give a false sense of security.
• GFCI instead of ground provides life-safety protection but does not help with surge protection and other uses of the ground wire.
• For bathrooms and kitchens (any location within 6 feet of a sink, tub or shower), always install GFCI, whether or not you have a ground wire available.
• Properly installed, GFCI only needs to be on the first receptacle in a circuit and all later receptacles are protected. Doing this right is not rocket science, but requires a bit of thinking instead of mechanically replacing everything.
• Old receptacle boxes may not be large enough for GFCI receptacles, and may not even be large enough for quality modern plain receptacles. Replacing boxes is easy in unfinished walls. In finished walls it gets more complicated, but not impossible, at least most of the time. There are rules for box fill, but the bottom line is that if you find it hard to fit new stuff in an old box, the old box is likely too small.

Answer 3

You should take look at the Temper Resistant GFCI, for added on protection.

They have mechanical device inside (Shutters) preventing "objects" from been inserted.

However, when the 2 gang up they can destroy anything :P

Answer 4

Don't make it harder than it is

Except maybe a little harder.

I'm sure 10 times a day electricians have a conversation like "Well, you could just install GFCI receptacles" and the customer decides "Well I don't need an electrician for that".

And you can guess where this goes wrong. GFCIs aren't quite as simple as that.

Now, the key point to GFCI is that GFCI is not a receptacle. It is a zone of protection which protects any number of outlets or loads.

GFCIs come in many form-factors: GFCI+breaker, GFCI+switch, GFCI "just a GFCI" and of course the receptacle with which you are familiar.

Yes, obviously a GFCI receptacle protects its own sockets. But all GFCIs can protect, really, an entire circuit. Heck, in Europe, one GFCI protects the entire house - although that has some, um, compromises.

This is done via terminals that every GFCI has, called "LOAD". If a load or several loads or outlets has its hot and neutral wire attached to the "Load" terminals of the GFCI device, then they will be protected by that GFCI.

That is the only thing "Load" should be used for.

Of course the novice who is smarter than the electrician watches a Youtube video or two and is putting a GFCI at every receptacle, and using the "Load" terminals anywhere there are 4 wires. And then a ground fault trips them all, and they never figure out how to get them all reset!

So, the trick is to use one GFCI to protect the whole circuit.

Easy mode is to use GFCI breakers if your service panel has modern breakers available. These are more costly than receptacles, though.

The second option is to carefully map every circuit (via trial and error disconnections). Locate the first receptacle past the service panel, and put the GFCI there.

Either case requires identifying all the receptacles on that circuit and marking the receptacles (as relevant):

 GFCI Protected
 No Equipment Ground
 Reset west wall this room

(the last line is purely optional). Making your own labels is legal so long as they are not handwritten.

And you are free to convert them to 3-prong outlets, even though they don't have a ground. Plain 3-prong outlets will suffice, but they probably need to be Tamper Resistant.

Or, grounds can be retrofit

But grounding protection is not as good as GFCI protection for humans.

Retrofitting grounds is allowed under certain fairly generous rules, and is handy when you have electronic equipment that needs grounding to suppress static electricity to reduce ESD damage.

Don't forget AFCI

AFCI is Arc Fault protection. It is designed to detect failing wire connections that are likely to start a fire. It "listens" electronically for the "sound" (waveform) of wire arcing. That can be just the thing for a house with old and suspect wiring, particularly if the wiring is aluminum.

(Other measures can help greatly with aluminum wire; I feel those + AFCI breakers make aluminum perfectly reliable).

AFCIs also can help with a child sticking 2 things in the hot and neutral slots, which a GFCI cannot detect if someone is being shocked between hot and neutral (the GFCI thinks that's just a normal load, but the AFCI notices the current curve isn't normal).

Answer 5

You specifically asked about "safest" given the context of 4 and 7 year old kids. The answer is ungrounded GFCI Receptacles.

• You would add a very valuable electrocution prevention feature that a well ground product still does not offer: The presence of a leakage current that might be leaking through a human. (Leakage Current means more than 6 milliamps of current flow is happening elsewhere, not being looped back through second prong of the plug.)
• You can save money on multiple GFCI Receptacles by updating "the first" ie. mapping out where the daisy-chain of several outlets begins. Upgrading the outlet first reached by the wire from the fuse box and connecting the downstream outlets on the optional LOAD side. Swap those with 3 prong outlets, and label them "No Equipment Ground" and "GFCI Protected" (You can find mapping advice elsewhere. Please confirm all imagined downstream outlets with a GFCI outlet tester.
• NOTE: Please also know that your house was wired to power powering desk lamps, not space heaters or air conditioners. They may work, but only voltage-drop measurements under load tests will detect degraded connections in the walls or service panel. Too much voltage drop means some connection is getting quite hot, which left unrepaired can burn your house down!

Ref: NEC 406.4(D)(2) Non–Grounding-Type Receptacles NEC Snippet

Answer 6

The US National Electrical Code allows GFCIs to be fitted with missing grounds in retrofits, but NOT in new installations.

What that says to me is that the people writing the code thought that GFCIs with missing grounds were a "lesser evil" than the realistic alternative of people using cheater plugs or cutting off ground pins but that they did not consider GFCIs a proper replacement for grounding overall.

Proper grounding and breakers should disconnect the fault as soon as it occurs, a GFCI with a missing ground cannot do anything until after the shock starts.

Also, grounds aside if the house was wired in 1955 and hasn't been rewired since I would be very worried about the condition of the wiring. Afaict 1955 was before PVC became common and old rubber often degrades over those kinds of timescales.