I have this surface mount wiring connected to an outlet through the bricks (bottom-middle in photo). I would like to branch from this to add a switch (through bricks) and go straight up into the ceiling & attic in order to install a ceiling light on the other side of the brick wall. My city uses the 2011 NEC. How should I run the wire into the switch and up into the attic to be compliant?

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Replace the elbow-piece -- it's really a type of conduit body called a LB (L for elbow, B for out the back) -- with a box and make the connections to the new wiring there. You may have to pull a new stub-length of THHN to the existing receptacles to get enough slack in the box on the existing incoming wires to make the junction.

As to the new run -- I'd use two lengths of conduit for the exposed run: one from the tap box to a box mid-span that serves as a tap point (I'd use a T body, but there's not enough space for it unless the conduit run is offset sideways from the switch location anyway) and the other from the upper box (it can be a handy-box as the box fill's minimal) to the attic, then use a nipple to stub off from the back of said handy-box to the box with the switch in it (which'll need to be capable of taking a conduit). A one-gang box should be more than adequate for the switch box, by the way. The wire would be THHN to match the existing circuit gauge, in standard colors (black/white) of course, with only hot (black) wires run to the switch location from the tap box behind it.

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  • ThreePhaseEel, Thank you very much! You mentioned THHN, but could I use NM-B inside the EMT conduit for the new run of wire? This way I could continue that same wire into the attic and to my lighting fixture? The attic above this is a flat roof so I have to fish the wire over to another section of my attic which has crawl space. Can I just insert the EMT through the ceiling and leave the end of it open, or do Ineed to terminate it with a box or something on the ceiling? – John Nov 23 '16 at 12:58
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    Since it's an indoor space, you can go ahead and run NM-B through the conduit, although I'd use THHN for the "stub" run to the switch to save having to retag a white wire. Also, you'll want a box where the conduit terminates in the attic, BTW. – ThreePhaseEel Nov 23 '16 at 20:20

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