pmcchesney
Member
- Location
- MN
I am adding a second story addition with 13 new circuits, a mix of 15A and 20A ckts. I ran 2-1" PVC conduits to the panel in the basement intending to wire the ckts in pairs with a common neutral, 14 ga and 12 ga THHN. I also pulled 2 10 ga stranded ground conductors. The conduits terminate in the attic at a 10X10X4 box. All the Romex wiring for the addition comes to that junction box in the attic. The grounds all terminate in a terminal strip in the jbox. My mistake is that most of the ckts have openings in the bedrooms and require AFCI's so they will require dedicated neutrals, and now I've read that the GFCI outlets in the bathrooms and on the deck also require dedicated neutrals so I need to install 7 more conductors in the pipes, a dedicated neutral for every circuit; for a total of 26 conductors plus grounds. It appears I will not meet code unless I derate all the conductors, my understanding is that when the pipe fill reaches 9 current carrying conductors, a 12 ga wire is derated to 20A and a 15 ga wire is derated to 15A, more than 9 CCC's and 12 ga drops to 15A and 14 GA below 15 A. I have a 3rd pipe available that was installed for low voltage, I could use it for the additional conductors. My question is...will the 3-1" PVC conduits be adequate for the conductors and grounds: pipe 1-8 CCC's + ground/pipe 2-8 CCC's + ground/ pipe 3-10 CCC's 15 A ckts wired with 12 ga conductors? Also, are 2 10 ga ground conductors adequate or should I pull more in? Thanks for any help...Pat
