I am looking to make the wiring updates in my home extremely simple to understand while doing so in a code-approved manner.

I cannot find anything against wrapping a thin band of colored electrical tape around the outer sheathing on NM-B wire such as a small band of red tape around the yellow jacket of the wire below at each junction/fixture to help identify which circuit each wire belongs to.


A colored electrical tape pack is what I was thinking of picking up: enter image description here

Basically, I was thinking of adding two thin colored bands to identify the main runs of the branch circuits (using up to six colors for each band: black, white, red, blue, green, and yellow). And then I was thinking of adding two more thin bands to identify the branch connections to receptacles off of the main runs. However, I am unsure if labeling the sets of 3 wires (for 12-2) with a couple small bands of electrical tape would be against code (such as wrapping the sheathing with green electrical tape since green is typically used to mark ground wires) or actually make it more confusing. Answers that include best (or typical) practices are very welcome (even if the typical practice is to not mark the wires at all).

EDIT: While I agree with the update to the title to make the question a little more general, I am still interested getting an answer to my proposed solution about using colored electrical tape bands from the perspective of the NEC (2008 or later). I certainly appreciate the answers that suggest labels on the wires, but case in point, my hand writing is terrible and I think color is a lot easier to identify at a glance than trying to read little numbers. The way my home is currently wired with knob and tube inspired the thought because the original wiring truly was in an extremely structured, well-crafted manner and is really a work of art to look at (each hot wire for each branch circuit of the existing knob and tube wiring is a different color that is both easy to understand and follow throughout the house). I plan to create a full set of "blueprints" (in color with color-coded wiring) and keep an updated printed copy of the diagram with the electrical panel so I am still favoring the idea of color-coding the wires if it is NEC-compatible.

  • Above all else, clear labels on the panel are very important, with complete info on what is controlled (eg, if it controls plugs in 3 different rooms, mark that down) -- and keep it updated! If it's not clear, marking the breaker # on the back of the fixture cover can be helpful. Having everything labelled is nice to turn of the correct circuit on the first try, but no matter what, if I do electrical work on something, I'm still going to verify with my voltage tester. Most residential wiring is not so complex that it can't be easily figured out, so consider the benefits vs work involved.
    – gregmac
    Commented Aug 19, 2013 at 21:27

3 Answers 3


As far as code compliance goes, you're fine. As long as you're only wrapping the tape around the outer sheathing, there is no problem. If you wrap colored tape around individual conductors (wires), you may start confusing people.

Just make sure you use good quality tape. Some of that cheap crap tape could end up falling off in the future, which could lead to confusion and possibly injury and/or death.

  • While I also find value in the other answers given. I am accepting this answer based on the answer to my original question. Also, since you speak to avoiding cheap tape, do you have any poor experiences with GardenBender brand electrical tape? That is what I picked up and it seems to be of reasonable quality.
    – user14416
    Commented Aug 20, 2013 at 17:13

I spent a couple hours this past winter mapping out my entire house.

The fields on my spreadsheet are as follows for each box in my house (lights, outlet, switch, garage opener, anything):

  1. Panel Breaker (examples A1-10, B1-10)

  2. Drop # - the first box on the branch is simply labeled 1, second box 2

  3. Notes - if I know how things are wired in the wall I will put a note like "wire goes straight up to attic from outlet"

  4. Room of the outlet - each room with unique name (Bedroom 1, family room, den...)

  5. Location of outlet in room - I use actual navigation directions and go from left to right on each wall. So an example would be "West wall outlet #2" - meaning there was outlet #1 to the left of that on the west wall.

  6. What the outlet does.

  7. Other notes - I have aluminum in some of the house so I marked these here and marked if I have an extra wire for fan.

I could see wrapping the branch with yellow tape with BRANCH written. You could also give every wire a unique code A1-4 = branch off of panel A1 and outlet #4. This becomes hard to conceptualize if your branches aren't daisy chained but still works with notes.

My wife thought I was nuts spending a few hours doing this but I have already saved a ton of time. If I need something off, I just pull up the spreadsheet. Also this allowed me to transfer some of the outlets to other circuits or to new circuits - I had 4-5 circuits with way too much on them. I am now down to 1 circuit that only has a little too much and would have never realized without the spreadsheet.

  • Definitely good advice on the level of detail to capture. I certainly wish I had notes like yours for the existing wiring in my home--especially the new wiring additions by one of the previous homeowners that are one of the primary causes for me to be rewiring everything.
    – user14416
    Commented Aug 20, 2013 at 17:10
  • @statueuphemism - This only took 2-3 hours and a lot of yelling.
    – DMoore
    Commented Aug 20, 2013 at 17:31
  • LOL @ "and a lot of yelling" :) With the modern convenience of cell phones & unlimited calling plans... Of course a Bluetooth head set is mighty helpful, too.
    – FreeMan
    Commented Oct 5, 2020 at 12:08
  • @FreeMan - my kids were helping. If I gave them a cell phone to speak into they would be playing a game within 30 seconds and once the game started they would just start answering things with nonsense yes and nos.
    – DMoore
    Commented Oct 5, 2020 at 18:49
  • A) Good on ya' for getting the kids involved, B) I understand the game thing, C) oops, this was 7 years ago...
    – FreeMan
    Commented Oct 5, 2020 at 20:40

We replaced the main panel in our house a few years back. Before removing the old wires, I wrapped a bit of masking tape around each Romex near the circuit breaker end with a note handwritten on it: NW bedroom, full bath, SW kitchen outlet, NW kitchen outlet, etc.

This made it quite easy to wire in the new panel and fill in the new panel's wiring label. Three different city electrical inspectors had a look at it in the years since: one for the pre-panel switchover, one for reconnecting the meter, and one when we added a bathroom about two years later.

The masking tape is still on the wires. Not one of the inspectors minded them in the least.

I should think electrical tape would be even more welcome. It is commonly used in certain junction box applications.

There is no marking on the remote ends of the wires. All we care about is which wire in the panel goes where in the house.

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