Garage Lighting - Wiring Question

[bmwman91]

So the house that I recently bought has a decent sized garage (for this area) and atrocious lighting. Houses were built with a single 60W bulb on a wall near the laundry area back in the 1950's. The PO converted the socket to an outlet that powers a pair of 48" T12 fluorescent's, but the fixture is old and I need more light.

So, I have 9 of these suckers on the way:

http://www.homedepot.com/p/Lithonia-Lighting-2-Light-Flush-Mount-White-Industrial-Fluorescent-Light-L-2-32-120-GESB/100165074

They will get used with some 4100K, CRI-85, 2950 lumen bulbs.

The plan is to install a new switch box that will house 4 switches. The 9 fixtures will be broken up into 4 groups since the way I am going to lay out the garage for tasks means that I won't need everything on at once in most cases, and my wife only ever needs light around the laundry machines.

Anyway, the existing switch box has the original 12-2 (no ground) running into it, and the new box will take this and split it to 4 switched outputs. The plan is to use 14-2 since the circuit is on a 15A breaker, and code only requires 14ga for a 15A circuit. 14ga is going to be easier to work with since, as of now, it looks like I need to get 5 conductors into a wire nut in four cases.

[Pantless Spency]

clamps and heat shrink definitely is not code-worthy lol.


why dont you just run wire from your existing power source to your switch boxes, then run a SINGLE wire from each switch to the multiple light sources you wish to supply power to? just daisy chain from one fixture to another and so on. that way you only have to have two wires in each wire nut.


i rewired a garage built in the 30's-40's in sacramento this summer and that is how i did it, and for circuit protection we wired the whole thing from one GFI outlet, so if anything in the garage at all shorted/fucked up the single GFI would trip out the whole garage electricity.



let me know if you have anymore questions i can provide pictures if you would like.

[ck_taft325is]

Yeah, I would do as Pantless is saying. Daisy chaining is far easier than having each individual light go back to each individual switch. Not to mention the load you're looking at pulling isn't much when you really add it up. Remember, you don't want an over abundance of heat in each wire. Cramming more wires into a relatively small box will just produce more heat.

Go 12-2 and run them all off of one 15a breaker. 9 lights is childs play ;)

[bmwman91]

Old confusing info removed...

[rturbo 930]

Per the rat's nest of wires in my OP, this is what I was thinking as far as grouping the lights. I want to keep group #1 pretty minimal since my wife tends to forget that she left the lights on when she does laundry, and I don't need to be burning up 750W overnight for no reason.

Have you thought about putting group 1 on a motion sensor?

And of course, I could keep the two lights by the door & laundry area on one switch, and the other 7 lights on another switch. That would be simple, and I am sure that it would only be a difference of like $10 per year in electricity. It would be easy to daisy chain everything that way.

Do this. No reason to have 3-4 groups of lights, and your wife doesn't need more than two on when doing laundry.

[AndrewBird]

Personally, I would do 1-3 on 1 switch and 4 on another. I bet you will find you have all the top lights on during normal use, rather than picking and choosing. The #4 row could be turned off though when the garage door is open and blocking those lights. Referring to this diagram:



Why do you want to be able to have some lights off anyway? Just to save power?

[bmwman91]

Haha yeah, my cheap-ass side is trying to influence me. Your suggestion makes a lot of sense. Really, what's the point of buying all the lights if they aren't all going to get used?! Having the 3 bottom ones separate so they aren't lighting the back side of the garage door is a good call. 2 switches is definitely a lot less of a pain in the butt to wire.

[Thizzelle]

your making it so confusing, I wire up my whole garage last year but trying to follow this is difficult. how long is the garage I don't think you need 9 lights, wow

[bmwman91]

Yeah, the fact that I even have to ask probably means that the idea I had is a non-starter. It's looking like it'll just be 2 switches. One for lights over the laundry machines and one for all the rest.

9 lights will make this a very well lit work space. It is going to be a good year or two (at least) before I put up sheetrock on the walls, so light reflection from the walls and ceiling is very very low. According to a GE lighting calculator, I am going to get ~65 footcandles (average) with the 9 fixtures. Once I get white walls in, it'll go up closer to 90fc. There may be plans for a loft above the garage though, which would ultimately involve structural changes, and I don't want to invest in finishing the walls if I am going that route.

Woodworking and machining projects benefit a lot from lots of light. My dad has a similarly sized garage with 6 fixtures like this, and at times it isn't quite enough when I am using his Bridgeport. I have to get a task light in there, but that can cast strong shadows, so I prefer to get things very uniformly bright.

[Thizzelle]

yeah, the fact that i even have to ask probably means that the idea i had is a non-starter. It's looking like it'll just be 2 switches. One for lights over the laundry machines and one for all the rest.

9 lights will make this a very well lit work space. It is going to be a good year or two (at least) before i put up sheetrock on the walls, so light reflection from the walls and ceiling is very very low. According to a ge lighting calculator, i am going to get ~65 footcandles (average) with the 9 fixtures. Once i get white walls in, it'll go up closer to 90fc. There may be plans for a loft above the garage though, which would ultimately involve structural changes, and i don't want to invest in finishing the walls if i am going that route.

Woodworking and machining projects benefit a lot from lots of light. My dad has a similarly sized garage with 6 fixtures like this, and at times it isn't quite enough when i am using his bridgeport. I have to get a task light in there, but that can cast strong shadows, so i prefer to get things very uniformly bright.

that's what i did, i have 3 switches, 1 for light on wall above laundry like you said, next for my overhead lights and last for my security drive way light. I only have 4 2 bulb fluorescents and it seems fine. sheet rocked my walls and painted them semi gloss bright white, it's nice. I have some sheet rock left over if you want to come pick it up, 6 pieces. PM me

[bmwman91]

Hmm, OK well since it is obvious that I was putting waaaaaaaaaaaay too much thought into things, I am going to set it up like that. KISS principle must be obeyed! One switch for the laundry lights, one switch for the rest. Thanks.

[Thizzelle]

also 3 circuits in the garage, 1 for left wall, 1 for right wall and 1 for ceiling & back wall

[bmwman91]

Makes sense. As Nitro mentioned, I probably want to have control of the ones that can be blocked by the garage door.

Does something like this look sensible? (using the term loosely since 9 lights in a typical suburban garage might not fit the definition lol) It seems to be what Nitro suggested.

[Thizzelle]

also what you do is not link one outlet to the next you want to do it with pigtails, like so

if you have a 4 gang then you have 2 pigtails coming off it.

[bmwman91]

Thanks, that was going to be my next question. Since pigtails are the accepted practice, that's what I will do.