Home DIY Extend an Electrical Outlet – Followup and Fixes

Extend an Electrical Outlet – Followup and Fixes

Extend an Electrical Outlet – Followup and Fixes

I extended an exterior electrical outlet in this post, which was also detailed in a YouTube video and was posted to Reddit. I got most of my comments on Reddit and a notable number of them offered up three specific criticisms. They are:

  1. The conduit connecting the two junction boxes need to be supported mid-way
  2. I didn’t leave enough wire poking through in the new junction box
  3. I need to use a GFCI outlet!

That latter one is by far the most serious, so I’ll address that in the most detail, later.

Here’s the video of my response:

Conduit Support

I was unable to find any NEC regulations specifying the support length for liquid-tight conduit, but it’s likely similar to that of flexible metal conduit. Both are flexible, at the very least. The NEC regulations for FMC say that it needs to be supported within 12″ of termination.

Technically, yes, my installation would be in violation of that particular code. There is a total of 16″ between the two termination points:

16" span between termination points

Meh. 16″ is close enough to 12″ when that’s the entire length of the conduit. I could see if this conduit was going to go for a few or a lot more feet… then it would absolutely need to be supported on the standard intervals. For such a short length, though, it’s massive overkill.

It’s kind of like when you are supporting a long length where you have your two offsets from the termination points but also the interval points within the length. Those will almost never perfectly match up, so you’ll end up having one interval that is notably smaller than it needs to be or a slight bit longer. That slight bit doesn’t matter.

Same with this bit. Those 4″ don’t matter.

Longer Wires

That’s a fair cop about the length of my wires in the new junction box. I left maybe 3″ of wire in the box, which is at least half of what it should be. That’s not a safety hazard at all, but it’s absolutely a pain to work with. I decided to make things easier on myself and on any future person working on this box to just extend those wires right now.

I did that by splicing a new 6″ length of wire to each of the hot and neutral wires and connecting them with a wire nut:

Extended wires in the new junction box

That makes it a lot easier to work with when installing the outlet.

Testing GFCI

By far the criticism of the lack of a GFCI outlet was the most serious. It’s very important to have ground fault protection on all exterior outlets since ground faults when working with tools outside aren’t very uncommon. Notably, though, I used two “normal” outlets in the new junction box.

I felt safe with this setup because the circuit itself protected. There is a GFCI outlet at the beginning of the circuit which protects the rest of the circuit, including these two new outlets.

That’s just me saying that without proof, though. Well, I have proof in the form of a GFCI tester.

This works by inserting the tester into an outlet that should be protected against ground faults and verifying that it has power:

Starting a GFCI test

Then I press the Test button and verify that the circuit is tripped and I no longer have power:

Showing the tripped GFCI tester after the trigger

And there we go! This circuit is ground fault protected.

Installing a GFCI Outlet

Well… there is still some valid reasons to use a GFCI outlet in that location. The first is practical — the GFCI outlet that gets tripped whenever there is a fault on any of the exterior outlets is on the other side of the house in one of our bathrooms. That’s kind of a pain. I have occasionally forgotten which outlet is the “master” one and even when I do remember, it’s non-ideal to have to trudge through the entire house just to reset a fault that happened somewhere outside.

The other reason is to just alleviate questions and uncertainty up front. The fact that so many people commented on the lack of a proper outlet shows just how much people expect to see one in that case. When it’s not there, then you can certainly demonstrate that it works with a tester… but it’d be easier all around to just have a GFCI outlet there in the first place. So I installed one.

New GFCI outlet

I don’t have a description of that here since it’s nearly identical to the installation from my original post, and I do show it happening (again) in the video. The only difference from a normal outlet is that it does matter which terminals are which, with respect to top or bottom. With normal outlets, as long as you have the hot and neutral terminals set, then you’re golden. With GFCI outlets, the incoming (“line”) wires must be installed in the top set of terminals while the outgoing (“load”) terminals must be installed in the bottom set of terminals. That’s the only difference.


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