I'm installing a flood lamp on my outdoor garage. So, I went to take look at the junction box, and to my surprise, it appears oddly filled:
Filled to the point where I almost feel as though it's too filled.
The junction box is 4x4x2 1/2. There's at least from what I can count 4 different circuits running out there:
1) washer + misc outlets in garage
2) dryer
3) garage lights (outdoor)
4) garage lights indoor + garage opener
The house was built in the 1980's – I live in the Pacific Northwest (specifically, Washington State).
I do have a 5×5 that I purchased that I could replace it with, but I wasn't sure if I should "extend it" or just "replace it" entirely, which I guess would be the second half of my question.
I'm adding the flood lamp to the same circuit as the rest of the outdoor garage lights.
Best Answer
The rules for box fill are contained in NEC 314.16(B). Generally, if you are using 14 AWG wire, you need 2 inches of space for
If the wire is 12 AWG, all figures are increased to 2.25.
If you do the math and your box has too many wires, including any you need to add, you need either a bigger box or a second box.
If appearance isn't an issue, you can get box extenders that protrude from the front and add inches.
Depending on how the wires feed into the box, you maybe able to add another box a few inches to one side or the other, removing a few circuits from the original box, terminating them in the new, and just connecting the live feed between the old and new.