Can I use Blanked-Out Gang Boxes That Seem Ready to Go?

August 24, 2020 5:40 AM

In my house that I am moving back to, there are five locations throughout the house that have "blanks" over single gang boxes. Inside the boxes are capped-off 2-wire Romex that is live. It appears as though they are wired for more outlets that were never installed. Can I put outlets there as long as I don't overload the breaker with the total draw of all devices? (Follow-up questions after the break.)

Also, why would this have been done? I know code states that you must be able to reach an outlet in each direction by 6 feet, so maybe the inspector saw the boxes there, signed off on it, then the installer was too cheap or ran out of outlets to actually install? These blanked-out boxes certainly would continue the every-12-feet- pattern if there had actually been outlets installed in them.

There is even one of these blanks with live wires behind the refrigerator, yet the refrigerator is plugged in much further away (I haven't tested to see if the blanked outlet and the used outlet are on the same circuit. In that case, I can see that they may have wanted to get the fridge on a different circuit than other appliances.)

Any other reason this would have been done this way? The house was built in 1939, but the Romex was put in during the 1988 major remodel and expansion. (I have owned the house since 2010, though.)

posted by TinWhistle to Home & Garden (8 answers total)

The code issue is actually that you can't "bury" a splice in the wire - that the splice needs to be contained in an accessible metal box. It is unusual to have such a large number of them, however - I would imagine you could put in an outlet there if you wanted, they may have just been plans for expansion. I've never heard of the "outlet every 6 feet" rule - the wiring probably runs dozens of feet from your breaker box just to get to the first outlet.
posted by scolbath at 6:47 AM on August 24, 2020

I'd recommend at least discussing with a local electrician to make sure you are aware of any code implications.
It is possible that the reasoning had to do with grounding. Since you have two wire, it sounds like you won't be able to put in grounded outlets. My understanding is that you may be able to put in GFCI with a label indicating it is not grounded (so that you know not to plug a surge protector in at those receptacles). I could see someone determining that it was better to simply blank those locations off during an upgrade to grounded outlets in the rest of a property. Certainly you would want appliances such as a refrigerator to be properly grounded.
posted by meinvt at 6:53 AM on August 24, 2020

Response by poster: Just some clarifications:

1) These aren't splices--they are the ends of runs in all cases;
2) 12-2 Romex is white, black, and ground, so there is a ground in all cases;
3) Code for a long time has been that in main living areas, outlets cannot be farther than 12 feet apart so that no matter where you stand, you have an outlet within 6 feet of you. People assume that this is because most extension cords are 6 feet.
posted by TinWhistle at 7:38 AM on August 24, 2020 [2 favorites]

Yes, it's a funny question. For the electrician finishing the outlets is the easy part. I would go along with your guess that the electrician on this project dropped out just before completion, for whatever reason. Maybe they left the boxes open for easier painting, then had a snag rescheduling.

In theory you could just install the outlets, but in practice I'd maybe pay a qualified electrician to take a closer look at it.
posted by ovvl at 8:37 AM on August 24, 2020

Best answer: You seem to know your way around electrical - understanding that 12-2 includes a ground, splice vs end run, etc.

If you can confirm where each capped end is coming from - i.e. what outlet is directly upstream, by disconnecting it upstream then testing continuity across the ends of the wires - go for it. Install outlets.

In the case of the fridge outlet, fridges are supposed to be on a dedicated breaker by themselves. Just FYI.

If I had to guess, the electrician didn't finish these because he didn't get his final payment.
posted by notsnot at 8:46 AM on August 24, 2020 [2 favorites]

Response by poster: Thank you all.

Ya, I know certain appliances and other things should be on their own circuit, but this was done in 1988. Nothing is on its own anything. :) (At least not until I have the energy to make it that way.)
posted by TinWhistle at 9:47 AM on August 24, 2020

Two suggestions:

Have you pulled the permit folder for your house? You may be able to get the info for the electrician who did the renovation. It might also give you other useful info.

I would install outlets if you don't find anything strange and can trace the wires back to the breaker. I would then use an outlet tester to double check. But at the first sign of anything strange, I would undo all my work and call in an electrician.
posted by sol at 9:49 AM on August 24, 2020

It can be useful, for future reference, to map out every switch, outlet and fixture in your house to determine which breaker circuit they are on in the panel box. You just turn off each breaker one at a time and figure out which locations are affected. This might give you a better idea of how these unused outlets are wired.

Once you have this map, is can be used to quickly isolate any future issues.
posted by JackFlash at 11:15 AM on August 24, 2020 [1 favorite]