Box Extensions- 4 Junction Square Boxes

[highkvoltage]

If you add a box extension to a 4" X 1 1/2" square box that gives an additional 1 1/2" how much wire fill do you gain? With out the extension you are allowed 9- #12? Would you be allowed 18-#12? I don't think you would be allowed to double the fill but I can't not find in the code the section that covers this. Thank you.

 

[caj1962]

Re: Box Extensions- 4 Junction Square Boxes

The extension ring you are using will have its volume stamped into it. While you may think it is unbelievable yes, you are doubling the volume of the box and ring you mentioned. The following code section applies;
(A) Box Volume Calculations. The volume of a wiring enclosure (box) shall be the total volume of the assembled sections, and, where used, the space provided by plaster rings, domed covers, extension rings, and so forth, that are marked with their volume or are made from boxes the dimensions of which are listed in Table 314.16(A).
(1) Standard Boxes. The volumes of standard boxes that are not marked with their volume shall be as given in Table 314.16(A).

 

[drmoody]

Re: Box Extensions- 4 Junction Square Boxes

Remember to account for clamps and devices when calculating proper fill. EGCs only account for one volume allowance. If you have a handbook, it has several pages dealing with box fill calculations. Article 314.16

 

[highkvoltage]

Re: Box Extensions- 4 Junction Square Boxes

I thought that's the way it was. I was just turned down on a job by the inspector here. He claims that box extensions aren't in the code and he doesn't accept them for use. I showed him both tables 314.16(A) and 314.16(B). I showed him the stamp on the side of the box extension he show me more red stickers. He then claimed I had to install GFCI's on every outlet in the kitchen including any that were dedicated. Frig, dishwasher and microwave and stormed of the job. He then on the reinspection started measuring my straps I used to hold up the MC cable looking to fail me again. He found one and I paid another fee. My lawyer now has the matter. I hate this inspector.

 

[a.wayne3@verizon.net]

Re: Box Extensions- 4 Junction Square Boxes

Come to pasco county Florida.We are having a growth explosion as my past posts have shown,I feel for you brother.Just get you ducks in line and go for it.You have no other choice !!!!!!

 

[a.wayne3@verizon.net]

Re: Box Extensions- 4 Junction Square Boxes

meant to say YOUR