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Discussion Starter · #1 ·
hi,

i am doing some remodeling, and had to move a 2 gang work box, 2 switches. when i removed the old box, it has one 12-2 feed, and six 12-2 romex feeding outside lights and an outlet. the two gang box was stuffed with wire! is this ok? should i put in a j-box next to the two gang or something to make more room???

bob
 

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hi,

i am doing some remodeling, and had to move a 2 gang work box, 2 switches. when i removed the old box, it has one 12-2 feed, and six 12-2 romex feeding outside lights and an outlet. the two gang box was stuffed with wire! is this ok? should i put in a j-box next to the two gang or something to make more room???

bob
Sounds like you need another box, or a box extender. Calculate the size of the box at 2.25 cubic inch per conducter, 2.25 CI for the ground (no matter how many wires), 2.25 CI for the cable clamps. Each hot and neutral entering the box counts as a 'current carrying conductor.' This will tell you how big a box you need. Sounds like 18.25 CI minimum.

Here is a box I found in my house. I just put an extender on it.
 

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Don't add another JB to the mix, just use the biggest box you can.

A 2 gang plastic nail on box will accept the wiring if it is done neatly. It's all about the make up. Inexperienced people can fill up a box with four cables where an experienced person could easily double that.

Open anothee stock 2 gang switchbox and take note of how the electrician made up the wiring and follow his methods.
 

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Sounds like you need another box, or a box extender. Calculate the size of the box at 2.25 cubic inch per conducter, 2.25 CI for the ground (no matter how many wires), 2.25 CI for the cable clamps. Each hot and neutral entering the box counts as a 'current carrying conductor.' This will tell you how big a box you need. Sounds like 18.25 CI minimum.
One feed & 6 12-2's - that's 7 wires + 2 switches

Ground = 2.25
Hots = 7 * 2.25 = 15.75
Switches 2 * 2.25 = 4.5
Neutrals = 7 * 2.25 = 15.75
***************************
= 38.25 - that's a lot....if my math is right

or does a device count as 2 (I think?), so 4 * 2.25 = 9
A total of 42.75....THAT is a LOT

I think the quad plastic blue box is rated at 32 ??

Plastic box, metal box? - does it have cable clamps?
 

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Six 2 wire cables out and a 2 wire in would be 15 conductor allowances plus the devices. Add 4 for the 2 switches = 19.
19 x 2.25 = 42.75 cubic inches. IIRC a plastic 2g = about 35 cu. in.
 

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One feed & 6 12-2's - that's 7 wires + 2 switches

Ground = 2.25
Hots = 7 * 2.25 = 15.75
Switches 2 * 2.25 = 4.5
Neutrals = 7 * 2.25 = 15.75
***************************
= 38.25 - that's a lot....if my math is right

or does a device count as 2 (I think?), so 4 * 2.25 = 9
A total of 42.75....THAT is a LOT

I think the quad plastic blue box is rated at 32 ??

Plastic box, metal box? - does it have cable clamps?
Ok, so my math was way off. :whistling2:

I'll do my math first from now on.
 

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The 2-gang plastic boxes I use are 36 cu in.

Here is a metal one that has 45 cubic inch capacity. You might want to consider using one of these:

 

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Discussion Starter · #10 ·
hi,

thanks for all the ideas! i bought a plastic zip box that is about 3/4" deeper than the original box. not sure of the cu in. i made sure all the wires, blacks, whites and grounds were not tangled in anyway, wired in the switches, wire nutted and tucked away in the back of box, worked out quite well.
 
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