Adding some new circuits in my attached garage

[JamieK]

Well, I'm finally adding some circuits to my attached 24' x 24' garage. I think I have a pretty good understanding of basic electricity, but would like some people to "look over my shoulder" to make sure everything is good. I hope thats okay!

I'm starting off with the lighting circuit. My plan is to have 9 Metalux 48" Flourescent 4 bulb fixtures aranged in 3 rows, each row controlled by a seperate switch. The rows are running paralell to the the joists. (In the photo, the joists are running left to right, perpendicular to the garage door.)This will feed off of a 20 amp breaker. All wiring will be 12/2 "Romex".

I have 6 of the nine lights hung, and have run the wiring next to the ceiling joists over to the eaves. I will need to wait on 3 of the lights for later, so can I just cap the wiring off with wire nuts till then? (Far left in the photo)

Here are the connections I've made inside the lights.

Next step will be to finish running the wiring along the eaves, back along the ceiling joist next to the main house, and down the wall to where I want the switches.

 

[volleyball]

I'd put up a temp. box where the next light is going to go. any screw hole will be covered by the light.

 

[Mustang51js]

Usually you only want an inch or two of the romex casing showing through the light but it's not a big deal the way it is.

 

[2ManyProjects]

Well, I'm finally adding some circuits to my attached 24' x 24' garage. I think I have a pretty good understanding of basic electricity, but would like some people to "look over my shoulder" to make sure everything is good. I hope thats okay!

I'm starting off with the lighting circuit. My plan is to have 9 Metalux 48" Flourescent 4 bulb fixtures aranged in 3 rows, each row controlled by a seperate switch.

It's obviously a bit late, since you have apparently already purchased those fixtures and gotten some of them installed; but I would have approached this project in a very different manner...

At 24'x24', I presume this is a more-or-less normal two-car residential garage. And from the photos, it appears you have the 9-10 foot ceiling height which is typical of such spaces. As such, the three rows of fixtures is a reasonable starting point, assuming they're placed properly (the outer runs 2-3 feet off the side walls, the third one right down the middle between the two parking bays). HOWEVER, I would have used TWO-tube fixtures, spaced as closely together as possible end-to-end (possibly even butting them tight to each other), AND added a fourth row running "crossways" a few feet off the wall opposite the overhead door(s). As it stands, you're concentrating a lot of lighting power into relatively few locations, with big gaps between them. That is likely to result in rather uneven light distribution.

I would also use an entirely different switching strategy. Rather than have each row be an "all or nothing" proposition, I would split ALL of the fixtures into three banks:

"Bank 1" would consist of some minimal number of fixtures (probably no more than two, three at the most, in a garage that size), which will serve as your "walk through" lighting. Switches for this bank should be located immediately adjacent to EVERY possible entry point into the space (including on both sides of any overhead doors). These are the lights you initially turn on when entering the garage, and provide just enough illumination to safely navigate through the space. And on those occasions when you're only running in to grab a screwdriver, bring in the groceries, etc., it will be all you need. Optionally, you can also set these up to be triggered by your garage door opener(s).

The rest of the general lighting should be split into at least two banks, on ROUGHLY an "every other fixture" basis, so as to still provide as even coverage of the entire space as possible, even when only one of these banks is in operation. I say "roughly" because, ideally, these two banks will NOT have an equal number of tubes/fixtures; but rather, one will have perhaps half-again to twice as many as the other. This way, you effectively have three selectable brightness levels between the two banks (much like a "3-way" light bulb). Hence, when your only doing relatively casual/non-critical work, you can run at a much-reduced overall brightness level, and save a significant amount of electricity (read: operating cost) in the process.

The rows are running paralell to the the joists. (In the photo, the joists are running left to right, perpendicular to the garage door.)This will feed off of a 20 amp breaker.

You really ought to use two 15A circuits for the lighting. That way, if/when one trips (or must be shut down for maintenance), you won't be left totally in the dark.

All wiring will be 12/2 "Romex".

That's overkill for a simple lighting circuit, but necessary if you insist on using 20A breakers.

 

[JamieK]

2ManyProjects, all of those are good ideas. Believe me, I thought about all kinds of different setups for this garage since I moved into the house a few years ago. I decided to go with this setup because its very similar to the garage I have been working out of, and am happy with it. I'm going to be using this garage as a workshop, so I centered each light above roughly where the wheel will be at, and over the workbenches. As for walk through lighting, there is already a incandescent fixture beside the entrance door into the house with a switch inside the house or I could switch on one row of the florescents. Also, with the three selectable rows, if I'm just working in one bay, I can turn on the two rows over it. Plus, it a relatively simple wiring setup for a novice like me.

 

[JamieK]

Next I ran the wiring through the joist bays over to the eaves, and along the eaves back to the joist bay adjacent to the house. Then ran it through that bay to a hole I cut above where I wanted the switches.

I then cut a hole in the top of the wall above where I wanted the switches. But I couldn't figure out a easy and safe way to run the wires so they would be completely hidden. I can't notch the bottom of the truss since its in the middle of the span. I thought about drilling through the truss and then another hole upward through the top plate, and snaking the wire though that. But that seemed like a pain to pull the wire through.

View from below

View from above

By the way, this is a modular home with a stick built attached garage. You're looking at where the two come together.

So what I'm going to do is place a small piece of drywall diagonally from the the ceiling to the wall, covering up the wires and holes. Kinda like a piece of crown molding. Another small piece on each side to finish it and paint it. Shouldn't be very noticeable. And it'll make it easier for any future wire runs.

 

[JamieK]

Sorry for the delay. Been busy and just now getting back to this project.

Next I ran the 12-2 down the wall behind the sheetrock to the opening I cut out for the switch box. I also ran the 12-2 down the wall into the crawlspace to be ran to the breaker later.

Installed the switchbox and pulled the 12-2 into it.

Does this all look all to code? To sum it up, I've got a single 12-2 coming from a (future) 20amp breaker into the switch box, feeding 3 switches. Each switch also has 12-2 coming off of it going to a seperate bank of lights.

I used the main ground wired in series to all three switches, and then used a wire nut to attach it to the grounds coming from the lights.

Used a wire nut to tie the 4 neutrals together.

And I used pig tails to branch the hot wire to the switches.