Hi, I have a quick question about box fill and common box volumes.
Working on our electrical rough-in, I just realized that some of the boxes I bought are a bit under-sized for where they will be used. I was also surprised that the wall box I planned to use most is listed as only 12.5 cu in. (2x3x2.5 in.)
What I find weird is that for this type of box, steel box with mounting clamp and internal NM clamps, this size is a common size at the home centers. Larger ones that are 2 3/4 and 3 1/2 deep are special order items. I would think with the limited use of a 12.5 ci box, the bigger ones would get used more, and also stocked at the store.
That made me doubt my calculations. But with a simple situation of a receptacle in the middle of a circuit run, I would have:
Two 14/2 nm > 4 cond > 8 ci
One recep > 2 cond > 4 ci
All ECG > 1 cond > 2 ci
Int clamps > 1 cond > 2 ci
Total: 16 ci required. Which means my 12.5 ci box is no good here. Yet it seems like there's plenty of space for this application.
So am I figuring this required volume right?
Any idea why a box with such limited application would be the one they stock while the larger versions are not stocked?
Thanks,
Keith
Working on our electrical rough-in, I just realized that some of the boxes I bought are a bit under-sized for where they will be used. I was also surprised that the wall box I planned to use most is listed as only 12.5 cu in. (2x3x2.5 in.)
What I find weird is that for this type of box, steel box with mounting clamp and internal NM clamps, this size is a common size at the home centers. Larger ones that are 2 3/4 and 3 1/2 deep are special order items. I would think with the limited use of a 12.5 ci box, the bigger ones would get used more, and also stocked at the store.
That made me doubt my calculations. But with a simple situation of a receptacle in the middle of a circuit run, I would have:
Two 14/2 nm > 4 cond > 8 ci
One recep > 2 cond > 4 ci
All ECG > 1 cond > 2 ci
Int clamps > 1 cond > 2 ci
Total: 16 ci required. Which means my 12.5 ci box is no good here. Yet it seems like there's plenty of space for this application.
So am I figuring this required volume right?
Any idea why a box with such limited application would be the one they stock while the larger versions are not stocked?
Thanks,
Keith
