Can I connect ground to my ungrounded porch?

Question

I live in a 40 year old house that has a porch added by the previous owner roughly 10 years ago. The porch contains two three prong outlets that have an open ground. Both outlets are protected by a GFCI on the first receptacle. When I bought the house the inspector found the open ground with a tester but noted that because of the GFCI it still met code.

I found the situation odd though because the GFCI outlet is connected to the incoming ground wire. And that circuit contains receptacles inside the house that are grounded. I followed the wires back to the house. Here's my best shot at a diagram:

inside - attic - closet - j1 - j2 - r1 - r2
closet - fan

The circuit inside the house runs up to the attic where there's a combination 3 prong receptacle / light fixture. Ground is good to this point. I did find that the fixture was wired with hot and neutral reversed and I fixed that. The ground wire exiting the box here is not connected.

The wire exiting the attic goes to an outside closet that looks original to the house. It contains a combination 2 prong receptacle / light fixture. The ground wire coming from the attic is loose here and cut short. There are two outgoing wires from this box. Their grounds are connected to each other but not to the incoming ground.

One of the wires exiting the closet goes to a ceiling fan on the porch.

The other wire exiting the closet goes through two junction boxes to the porch receptacles. All the grounds are connected in these boxes.

So ground is connected everywhere execpt between the attic and closet where both ends of the ground wire are loose.

My guess from all this is that the circuit originally ended at the closet. There was no need for a ground in the closet so the electrician cut it short in the closet and didn't bother connecting it in the attic. The porch addition was wired as though ground were available and then just never connected to true ground.

Is there any reason why they didn't connect it? Is there any reason I shouldn't connect it? The ground wire is cut slightly short in the attic but there's enough that I can connect it without any trouble. It's too short to connect in the closet though. I'd have to either get someone to run a new wire or extend it. Can I just attach a couple more inches with a wire nut?

Answer 1

Lighting branches didn't require grounds back then, so that probably explains why your closet was left ungrounded (I'm assuming there's no receptacles in there). My house was built in 1987 and I've fought a few ground battles on lighting circuits as well.

There should be no issue connecting your grounds. It's possible that your ground's continuity is broken somewhere else along the circuit that you're unaware of, but this would make you no worse off than you already are.

Once you connect your grounds, go back through and use a multimeter or a receptacle tester to verify the grounds are no longer open.

You can certainly use a wire nut, or some other acceptable means, to extend your short ground wire. This is called a pigtail and is quite common. If you do this, don't stop at a couple of inches-- go ahead and add enough so there is about 6" of ground wire as measured from where it enters the box, or where there is at least 3" extending past the edge of the box.