[tigereye]

All,

Wondering if I could get some feed back on the wiring plan for my attached garage. The garage walls are finished, so I'm running 1/2" EMT to replace all of the existing wiring and fixtures (3 ungrounded receptacles and 2 overhead ceramic bases).

The power will come from a new sub-panel that I'm installing in my basement next to the existing panel. I had been debating the sub vs service upgrade issue, but I'm not 100% comfortable that I understand the grounding implications of a service upgrade, so I'm going to go with a sub for now, as I'm doing some other work in the house, and need to use the garage for sawing, etc, and am tired of running extension cords into the house to do it.

My original plan was that the sub would be in the garage, but now I'm going to put it in the basement and start moving circuits over to it to get rid of all of the Aluminum in the house assuming that I'll upgrade the service at some point and will then move the sub elsewhere.

Anyway, my plan was to run 12 ga romex through the unfinished part of the basement to a junction box where I'll splice into 12 ga THHN that will run across the ceiling of a small finished hallway in the basement and then throughout the garage.

I'm using 12 ga. for both circuits because I figure I only need about 150' total (if that) of each color, but may end up needing to buy 500' spools to be cost effective at the local box store, so don't want to do that for both 14 and 12 ga.

Questions that come to mind:

Are there too many outlets feeding off of the GFI on the red circuit? I had heard that 5-6 was preferred. I can throw another into the mix if needed.

Is the garage door circuit ok on the lighting circuit, or should it be by itself?

The new lighting will be overhead fluorescent shop lights.

Thanks,

Mike

 

[Bocolo]

I am not an electrician but here is my input. I believe 12 outlets or less on a circuit should be fine on a regular run but am not sure on a GFCI circuit. If you are running only 12 agw wire why not make them all 20 amps instead of a section on 20 amps and another section on 15 amps? I believe your switch is on the wrong side of the door. How much power does your garage door pulls? My personal preference is to plan on the future and if it is going to be just as easy to pull two new runs as three runs then why not pull three runs? Thanks.

 

[J. V.]

I would not do this as you propose. But, you can put your sub where you want. If it were me, it would go in the garage.
If you are only going to run a 20 amp circuit to the garage, at least use a MWBC. This will give you two separate 20 amp circuits. Plenty for what is on your drawing. Since the garage is attached it really doesn't matter if you use a sub panel, 20 amp circuit or multiwire ciruit.
What size main service do you have?

 

[tigereye]

I would not do this as you propose. But, you can put your sub where you want. If it were me, it would go in the garage.
If you are only going to run a 20 amp circuit to the garage, at least use a MWBC. This will give you two separate 20 amp circuits. Plenty for what is on your drawing. Since the garage is attached it really doesn't matter if you use a sub panel, 20 amp circuit or multiwire ciruit.
What size main service do you have?

Ideally I'd agree, I'd like the sub to be in the garage. But my reasoning for not putting it there is that in addition to the garage, I'm eventually looking to redo a finished part of the basement into a media room, as well as start moving circuits off of the Aluminum branch wiring that's currently in 90% of the house. I was thinking that if I centrally located the sub in the basement, I could use it for all of these purposes.

I'm actually proposing to run two, and possibly three circuits to the garage. One for receptacles, one for lighting, and one possibly for the opener.

My main is 100 amps. I'm in the process of working up my currently usage, but I've not finished it yet.

Probably the optimal solution is to upgrade to 200 amps and a 40 breaker panel and be done with it. My concern with that is that I'm not confident that I fully understand what that upgrade means from the aspect of grounding the house (bonding to pipes vs the existing ground rod vs a new ground rod(s)), so was planning to stay conservative with the sub panel rather than charging into the unknown. :yes:

Regardless, my garage plan is likely to be similar either way unless I hear otherwise.

 

[hayewe farm]

Here's something to consider. If you are going to use your garage as a shop you may have need of 240 V in the future. A sub is not that expensive but rewiring is. Put a sub in the basement if you want and another in the garage. Run a larger 240 service to the garage sub. That way you are set up for any changes you need in the future and if you trip a breaker while working you don't have to go to the basement to rest.

 

[Scuba_Dave]

You can have multiple subs
I'd run a small 240v sub to the garage
Then install another sub in the basement
You could install a 200a sub in the basement & feed it with say 50-60a. Then when you are ready to upgrade to 200a you alread have a new main panel in place

If you are buying a spool of 12g wire then I would make the lighting circuit 12g 20a also & maybe run an outlet off that

I'm also planning on putting recessed cans in my garage & using CFL bulbs instead of tubes. I currently have T-8 fixtures that use 96w with (3) tubes. I can install (6) cans & 13w daylight bulbs, this will spread the light out more & use less power
And I can upgrade to brighter CFL's if needed

 

[qbert]

Your set up may be ok but be aware of voltage drop when running circuits 100' or more

 

[stubborn1]

One thing to consider - if you are going to have an extra refrigerator or upright freezer in the garage, you may want to install a dedicated circuit for it.

 

[tigereye]

You can have multiple subs
I'd run a small 240v sub to the garage
Then install another sub in the basement
You could install a 200a sub in the basement & feed it with say 50-60a. Then when you are ready to upgrade to 200a you alread have a new main panel in place

If you are buying a spool of 12g wire then I would make the lighting circuit 12g 20a also & maybe run an outlet off that

I'm also planning on putting recessed cans in my garage & using CFL bulbs instead of tubes. I currently have T-8 fixtures that use 96w with (3) tubes. I can install (6) cans & 13w daylight bulbs, this will spread the light out more & use less power
And I can upgrade to brighter CFL's if needed

Dave,

Your 200a idea is pretty much what I was thinking... Buy a big 200a 42 slot panel and use it as my sub for now fed off of a double 60 and then when I figure out my grounding questions, or get the money to hire somebody to figure it out, then it's just a matter of moving the service.

In the mean time, since you say that I can have multiple subs, can I run a sub off of a sub, so that I could go ahead with the 200a panel idea and then run the garage sub off of that? Sounds to me like that would be the best of all the options, as it meets both of my wants.

I hadn't thought about using cans in the garage. That would actually work really well since my finished ceiling is <8' at headroom is an issue. Are there any environmental concerns about doing that due to temperature/condensation/etc? While the garage is insulated and heated, it can still get chilly in the winter.

I'd planned to use the 12 ga for the fixtures, but was going to throw it on a 15a breaker since lighting doesn't typically draw a lot. But, I guess there's no reason not to use a 20a since the breaker cost difference is minimal.

Mike

 

[Scuba_Dave]

Well now I have to rethink my garage cans idea - for me
I have living space above the garage, so I need 5/8" sheetrock as a firestop. I'm not sure if recessed cans are allowed, if they have to be airtight (they would be anyways) etc

Do you have living space over the garage?

You can run a sub from a sub - as far as I know - anyone?
I think it is somewhat frowned upon, but it's a nice solution as a "Temp" measure until you upgrade

 

[goose134]

I agree with JV. Distribute two circuits around the garage. Lord knows you don't need a dedicated outlet for an opener (unless you have a Kong sized door). Two circuits should be plenty.

Please remember NOT to bond the neutral to ground in your sub panel.