Wiring Question (Adding New Receptacles in Garage)

[Martina]

Hi, everyone,

We recently added garage cabinetry with a workbench, however, there are no outlets in the vicinity. I'd like to introduce two new receptacles above the workbench but wanted to get some input before proceeding. We currently have two ceiling receptacles, one of which I'd like to tap into in order to pull power for the new outlets. My preferred way would be to pigtail at the outlet in the attic and simply drop a single 12/2 down to each new receptacle. Not sure though if this is an acceptable way of doing it. I'm going to attach a wiring diagram that shows the current configuration and two proposed wiring schemes (you will need to click on the picture and drag it down to see the top portion of it). Also adding photographs of the current setup in the garage. Any input would be greatly appreciated.

Thanks!

Martina

 

[wwhitney]

FWIW, the current NEC would require your ceiling receptacles to be GFCI protected, there's no exception in a garage based on the height. It also requires the GFCI controls to be readily accessible, so no GFCI at the ceiling. On the other hand, if those receptacles were installed under an earlier version that didn't require GFCI there, I think they can remain as is unless you replace the receptacle.

As to the two wiring patterns, the only downside to coming out of the middle of your existing daisy chain with 2 new 12/2 wires is box fill. The existing box fill calculation is 2 (12/2 cable) + 2 (12/2 cable) + 1 (EGCs) + 2 (receptacle) = 7 * 2.25 (for #12) = 15.75 in^3. If you add 2 more 12/2 cables, it becomes 11 * 2.25 = 24.75 in^3.

So if the existing ceiling box is over 24.75 in^3, no problem. If it's under, you'd need to enlarge the box, or pick a wiring pattern.

Cheers, Wayne

 

[Sponsor]

 

[Martina]

FWIW, the current NEC would require your ceiling receptacles to be GFCI protected, there's no exception in a garage based on the height. It also requires the GFCI controls to be readily accessible, so no GFCI at the ceiling. On the other hand, if those receptacles were installed under an earlier version that didn't require GFCI there, I think they can remain as is unless you replace the receptacle.

As to the two wiring patterns, the only downside to coming out of the middle of your existing daisy chain with 2 new 12/2 wires is box fill. The existing box fill calculation is 2 (12/2 cable) + 2 (12/2 cable) + 1 (EGCs) + 2 (receptacle) = 7 * 2.25 (for #12) = 15.75 in^3. If you add 2 more 12/2 cables, it becomes 11 * 2.25 = 24.75 in^3.

So if the existing ceiling box is over 24.75 in^3, no problem. If it's under, you'd need to enlarge the box, or pick a wiring pattern.

Cheers, Wayne

Wow, thank you so much for your detailed response! I appreciate your time and efforts.

The ceiling receptacle was installed by the builder back in '99, so I'm guessing we're still good on that since it passed inspection.

Never even considered box fill. Thanks for pointing that out! Would it be possible to simply add a larger junction box next to the ceiling outlet where I could safely tuck away all the pigtails? Just curious to see if that's even an option. If not, then I'll probably just proceed with wiring option # 2 which would also enable me to add a GFCI above the workbench since it will be the first outlet after the breaker.

Thanks again for your time and input.

 

[Reach4]

Probably overkill, but for future expansion, you could consider a sub panel in the garage. So when you buy that welder or electric car, you could wire them up. I am not looking to overcomplicate your project.

 

[wwhitney]

You could add a junction box in the attic, but that's definitely less elegant. Option 2 is preferable.

Cheers, Wayne

 

[Fitter30]

Check breaker size before wire size. 15 amp #14. 20 amp #12

 

[Martina]

Probably overkill, but for future expansion, you could consider a sub panel in the garage. So when you buy that welder or electric car, you could wire them up. I am not looking to overcomplicate your project.

Great suggestion! Thank you for posting.

 

[Martina]

Check breaker size before wire size. 15 amp #14. 20 amp #12

It's a 20 amp breaker, so I'll be using 12/2. Thank you for your feedback!

 

[Martina]

You could add a junction box in the attic, but that's definitely less elegant. Option 2 is preferable.

Cheers, Wayne

I agree, plus it gives me the option of adding a GFCI! Thanks again, Wayne- I appreciate all your input.