So I'm ordering a whole bunch of junction boxes for the house and running into an issue with how many wires I can fit in a junction box. So I'm doing retro boxes (maybe that's my first problem), and using 12 gauge for most of the circuits, and the wall depth only allows 3.5" which I found at home depot a 14 cu inch box which fits, the 21 cu inch box doesn't (requires 3.75")
With the 14 cu inch box that basically lets me have a 12-2 coming in, a 12-2 going out, but not another 12-3 for my 3-way switches. I calculated each 12 gauge conductor as 2.25 and assuming 1 switch in a 1 gang box, another 2 cu inch. Basically it looks like I need at least a 16 cu inch box to do a 3 way switch? I had planned on running a seperate 12-3 for the 3 way lights, but not sure if there is another way I can finagle the wiring?
Also are these retro boxes with the tabs junk? Nothing worse than plugging in an outlet to have the box move on you. But the alternative of tearing out enough space to physically attach a new junction box to the stud is not appealing.
*edit* Even if I switched to 14 gauge, I'm still over the limit in a 14 cu inch box.
I used this for the calculations:
http://ecmweb.com/code-basics/box-fill-calculations
With the 14 cu inch box that basically lets me have a 12-2 coming in, a 12-2 going out, but not another 12-3 for my 3-way switches. I calculated each 12 gauge conductor as 2.25 and assuming 1 switch in a 1 gang box, another 2 cu inch. Basically it looks like I need at least a 16 cu inch box to do a 3 way switch? I had planned on running a seperate 12-3 for the 3 way lights, but not sure if there is another way I can finagle the wiring?
Also are these retro boxes with the tabs junk? Nothing worse than plugging in an outlet to have the box move on you. But the alternative of tearing out enough space to physically attach a new junction box to the stud is not appealing.
*edit* Even if I switched to 14 gauge, I'm still over the limit in a 14 cu inch box.
I used this for the calculations:
http://ecmweb.com/code-basics/box-fill-calculations
