I want to extend some wires to relocate some switches. Normally one might do this by splicing new wires in and covering the junction box with a cover plate.

Is there a way to permanently splice wires together such that the splices don't need to be accessible?


2 Answers 2


There's no code compliant way to splice wires, without the splice being accessible.

If you're fishing the cable, and it can be pulled back out easily, or the wiring is exposed. You may be able to use a special splice. But that does not apply in this situation, since you're working in an existing box.

  • He's not in an existing box because he's "relocating switches". Is the connector recommended by the other answer somehow not code compliant if the OP is removing an old box, making a splice inside the wall at that location and moving the switch somewhere else?
    – JPhi1618
    Commented Oct 30, 2015 at 12:36
  • @JPhi1618 See my comment on the other answer. These splices cannot be used in this situation.
    – Tester101
    Commented Oct 30, 2015 at 12:48

I'm putting this up as an answer, mostly because there wasn't enough space in the comments. If I'm completely misunderstanding, please point it out, so that I and others might learn.

The big box stores in the US sell something called the Tyco Electronics Romex splice kit. (Model # CPGI-1116377-2.) They say the following:

Tyco Electronic's Non-metallic splice and tap kits provide a fast and reliable method for splicing or tapping 2 wire w/ ground and splicing 3 wire w/ground non-metallic cables up to 300 volts. They are designed and approved for use in rework within existing structures. Splice and Tap Kits also eliminate wire nuts for installation and replace the conventional method for adding a splice or tap for non-metallic cable without the need for exposed and unsightly junction boxes. NEC approved Article 334-40b.

  • 2 Wire Ccnnection

  • For Use On 12 or 14 AWG (300 Volt) 2 wire NM cable with ground

  • Eliminates junction boxes and wire nuts

  • Fast & simple to install

  • NEC compliant - article 334-40b, 2005 & 2008 NEC

  • UL & CSA listed

NEC 334.40(B) Devices of Insulating Material. Switch, outlet, and tap devices of insulating material shall be permitted to be used without boxes in exposed cable wiring and for rewiring in existing buildings where the cable is concealed and fished. Openings in such devices shall form a close fit around the outer covering of the cable, and the device shall fully enclose the part of the cable from which any part of the covering has been removed. Where connections to conductors are by binding-screw terminals, there shall be available as many terminals as conductors.

I think it's generally sensible to use junction boxes, but it seems like this product would be technically permissible.


((edit, following comments...)) It turns out that the wording of the NEC is subtle and specific for a reason. It talks about "...concealed and fished...", which @tester101 pointed out means that the wire can't be stapled in place (ie, it has to have been fished in). This would seem reasonable, as a stapled wire couldn't be pulled back out for inspection/repair/whatever. So, I'd have to imagine that an AHJ would legitimately fail this particular application because the wires would be stapled below the junction box and any holes in the framing may not let the join pass through.

  • 1
    "without boxes in exposed cable wiring and for rewiring in existing buildings where the cable is concealed and fished." These are not applicable in this situation, since the wiring is not exposed, nor is it being fished.
    – Tester101
    Commented Oct 30, 2015 at 12:48
  • 1
    @Tester101 It seems like "where the cable is concealed" is the operative part of that description. Sure the connector is strong enough to be fished, but I don't see how splicing it and then concealing it in a wall rather than fishing it into place is an issue.
    – JPhi1618
    Commented Oct 30, 2015 at 13:13
  • 1
    Because if it's fished, the cable will not be stapled in place, and so can be pulled back out of the wall. These splices are only allowed if the wiring is exposed, or where concealed it is fished.
    – Tester101
    Commented Oct 30, 2015 at 13:24
  • 1
    Thanks @Tester101 -- the part about fishing (and subsequent possible removal) had escaped me. I'll edit my answer to reflect that fact. Commented Oct 30, 2015 at 13:43
  • 1
    @JPhi1618, for starters, the instructions are printed under an electron microscope. Seriously, very difficult to read. The assembly is not straightforward. Maybe I'm doing wrong, but first impression was a POS product.
    – Kris
    Commented Oct 30, 2015 at 15:17

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