DIY Lighting - 20x20

[Austin_Jim]

Folks,

I posted a thread asking about suggestions for my new shop and got some great help. Now I am starting to look at lighting. This house is currently being built by a production builder. Not custom, so I can not do everything I want, but they have been fairly accommodating.

The house has (2) 2 car garages. One will be for my daily drivers and the other as a shop to wrench on cars.

The builder is putting more outlets in for me and also putting in (2) 220 receptacles. However (and this I find weird), they will only install (1) fluorescent light in each garage. Not a big deal I figure as I can add additional lights (I think). I am by no means an electrician, but have no problem getting my hands dirty on repairs and am pretty handy.

Question: How hard is it to add additional lighting wired to the one light that will be put in? The garage is 20x20, so I know I will need plenty more light, but I don't think I need separate 'zones'. I know fluorescent can be 'strung' together, just not sure how hard it is to do. I am not sure how many can be strung based on the circuit breaker size. Any suggestions? And can a larger breaker be installed? I am already getting a "service upgrade" that comes with them doing 220, so I don't think it will overload the panel.

Sorry if these are silly questions. I'm new to home electric and wiring other than large home theater systems. If this was a car, I would need to ask. 12V is just not as dangerous.

Thanks,
Jim

 

[2ManyProjects]

Folks,

I posted a thread asking about suggestions for my new shop and got some great help. Now I am starting to look at lighting. This house is currently being built by a production builder. Not custom, so I can not do everything I want, but they have been fairly accommodating.

Minor correction: You near-certainly CAN do everything you want; it's just probably not cost-effective to have the builder do so.

The house has (2) 2 car garages. One will be for my daily drivers and the other as a shop to wrench on cars.

That should help simplify things, as the "daily driver" garage won't need anything very ambitious.

The builder is putting more outlets in for me and also putting in (2) 220 receptacles. However (and this I find weird), they will only install (1) fluorescent light in each garage.

That is very likely because he doesn't want to pay for those extra lights, or the extra costs he would incur to install and wire them. That job would be somewhat time consuming; and to him, "time is money". So in an of itself, this is probably no big deal. HOWEVER... It just MIGHT also imply that whatever branch circuit he's planning to run that one fixture on is already shared between so many other loads around the house that he is leery of overloading it if he adds a bunch more fixtures. THAT is something you need to nail down NOW, regardless of who winds up installing the additional fixtures. Were it my house, I would insist on a separate dedicated lighting circuit for each garage, PLUS at least two dedicated 20A circuits for the general-purpose outlets in at least the "wrenching" garage (one such circuit would surely do it in the "daily drivers" garage; but two wouldn't hurt). Do not attempt to mix lighting circuits and outlet circuits. Also, the two 240V outlets MIGHT need to be on separate circuits, depending on what you plan to do with them (which will also determine what their current capability should be, and thus what AWG wiring will be needed for each of them); as it stands, we don't have enough information to know.

Once these circuits are properly roughed in, you can very probably install the lights and the outlets yourself, if need be. But you gotta have the right basic infrastructure in place FIRST.

Question: How hard is it to add additional lighting wired to the one light that will be put in? The garage is 20x20, so I know I will need plenty more light, but I don't think I need separate 'zones'.

You might not need separate "zones" in a space that small; but you will near-certainly want some control over the brightness level in use at any given moment, even if that is as simple as having one lamp switched separately to act as your "walk through" lighting, with everything else (comprising your "get to work" lights) on another switch. (Personally, I'd break it up even more than that; but the point remains.) In any event, you near-certainly do NOT want to "daisy-chain" everything off that one initial fixture; not because it would be unsafe, but because it would almost certainly force a somewhat undesirable overall fixture layout and switching arrangement.

I know fluorescent can be 'strung' together, just not sure how hard it is to do. I am not sure how many can be strung based on the circuit breaker size. Any suggestions? And can a larger breaker be installed? I am already getting a "service upgrade" that comes with them doing 220, so I don't think it will overload the panel.

As noted above, the main thing is to make sure you have the proper number of circuits, each of adequate capacity for its intended purpose, running into each garage space. Once that's done, the rest is relatively easy. The specific details will depend somewhat on the fixtures, and the layout.

If your builder is giving you grief over installing the lighting and outlet circuits you really want, ask him if he will leave at least the ceiling (and probably the walls as well) "open", and give you a credit against the drywall work he's NOT doing. Apply that credit toward the cost of getting those extra circuits roughed in from the breaker panel, even if they (temporarily) just terminate in capped off wires in one or more junction boxes. Then, after you take possession of the house, install your lights and outlets the way YOU want them to be, finish off the branch circuit wiring, and hire someone to finish off the drywall (or DIY it; but drywall can be a messy PITA, and is "fussy" for an amateur to get right).

Sorry if these are silly questions.

No such thing, really. The only stupid questins are the ones you either don't ask, or ignore reasonable answers to.

I'm new to home electric and wiring other than large home theater systems.

And unfortunately, much of that field is absolutely rife with "voodoo engineering" (cf. "Monster Cable" and other such marketing-driven nonsense); so you just might have some bad habits to "un-learn".

If this was a car, I would need to ask. 12V is just not as dangerous.

You might be surprised.

http://www.latitude38.com/LectronicLat/2007/0807/Aug13/Aug13.html

I can't swear that either of these fires were necessarily started by the vessels' DC electrical systems; but in at least the first case, it seems a distinct possibility.

Never underestimate the power of CURRENT.

 

[Austin_Jim]

2ManyProjects,

Thank you so much for your input. I am a total neophyte at home electrical. I great ly appreciate it. How about this? Have them give me another plug in the ceiling that is on it's own circuit that is controlled by a light switch. This allows me to have the 'stock' light on one switch for my 'just walking through' light and a second, I can wire in the rest of my lights off that outlet. I am thinking 9-12 4 ft dual T8s. How large do I need that circuit?

Thanks,
Jim

 

[pattenp]

You need to know the amp draw of the ballast in the fixture. The 4ft 2 lamp T8's pull around a 1/2 amp. A 15A circuit will handle up to 24 fixtures if each fixture draws no more than 1/2 amp. That's loading the circuit to 80%. Also I think you'll find for a 20X20 garage that 8 of the 4ft 2 lamp T8 fixtures will be enough.

Edit: I forgot to say I have 6 of the 4ft 2 lamp T8's in my 20X20 shop and they provide plenty light for me.

 

[Austin_Jim]

Thanks pattenp. Honestly, 8 would do the trick, but I'd rather have too many than not enough.

My plan is to do three rows of 3 or 4 lights; one in the middle, and one on each side as far as I can spread them toward the walls to avoid just the top of the car getting the light.

Do you have a picture of your garage lit up? I'd like to see how much light you have with (6) lights.

-Jim

 

[Vinci]

I have a 20'x20' myself and put 5 8' (4x4') fixtures in this past spring. That is a total of 20 4' tubes. I find that that is plenty for wrenching.

I wired mine with 4 of the fixtures on one switch and the fifth on another. That way, if I'm just popping out to the garage to get a tool or something out of the car, I don't need to light up all 20 of them.

 

[pattenp]

I'll take a picture tonight. But usually a camera will not get the true brightness to the eye because of the exposure time.

Edit: I took this while it was still light outside but I closed the big door so not to get any outside light. It was bright enough that my camera used 1/60th second shutter speed. I hope this gives you an idea.

View media item 33846

Thanks pattenp. Honestly, 8 would do the trick, but I'd rather have too many than not enough.

My plan is to do three rows of 3 or 4 lights; one in the middle, and one on each side as far as I can spread them toward the walls to avoid just the top of the car getting the light.

Do you have a picture of your garage lit up? I'd like to see how much light you have with (6) lights.

-Jim

 

[2ManyProjects]

2ManyProjects,

Thank you so much for your input. I am a total neophyte at home electrical. I great ly appreciate it.

Happy to help.

How about this? Have them give me another plug in the ceiling that is on it's own circuit that is controlled by a light switch. This allows me to have the 'stock' light on one switch for my 'just walking through' light and a second, I can wire in the rest of my lights off that outlet.

That could work, in a pinch; but it would not be what I would consider an ideal solution. For one thing, it still doesn't give you all that much flexibility, in terms of switching.

Also, per code, ALL duplex outlets in garages must now be on GFCI circuits -- including any which are mounted in the ceiling to serve such plug-in lamps. Yes, I think that is silly in the extreme; but it is what it is. I've also heard anecdotal evidence that GFCIs can sometimes be a problem with fluorescent lights.

Hardwired lights do NOT require GFCI protection, and will make for a much neater installation without all those ugly cord loops hanging everywhere; they will probably also be more reliable in the long run (think corroded contacts, weakening spring blades, etc.).

I am thinking 9-12 4 ft dual T8s. How large do I need that circuit?

A single 15A lighting circuit will be adequate for that. You can use multiple circuits if you want to, and there is at least one plausible reason to do so (maintaining SOME lighting even when one breaker has tripped or is thrown for maintenance); but you don't NEED to.

Thanks pattenp. Honestly, 8 would do the trick, but I'd rather have too many than not enough.

The Hot Rodder's Maxim:

If 'some' is good,
and 'more' is better,
then 'too much' ought to be just about right.

My plan is to do three rows of 3 or 4 lights; one in the middle, and one on each side as far as I can spread them toward the walls to avoid just the top of the car getting the light.

A reasonable basic plan.

I would suggest that if you go with three fixtures per row, the center fixture in the center row should be on its own switch, to be your "walk through" lighting. A second switch can control the end fixtures on the outer rows; a third switch controls the end fixtures on the center row and the center fixtures on the outer rows. If you go with four fixtures per row, just wire the center two in each row in the same manner as the center "one" would be in the nine-fixture setup. Either way, this will provide you with a good deal of flexibility in terms of how much light to make (and how much juice to use) at any given moment.

Do you have a picture of your garage lit up? I'd like to see how much light you have with (6) lights.

You really CAN'T judge from a picture. Unless you are a real expert photographer (and maybe even then), the camera's metering and exposure controls will skew things enough to make comparisons meaningless. See http://www.garagejournal.com/forum/showpost.php?p=3399950&postcount=6 and http://www.garagejournal.com/forum/showpost.php?p=3402563&postcount=10 for a recent example.

 

[TheMangler]

Ive got a 20x20 that I just installed a subpanel and 6 - 8 foot T8 lights into. It had the standard single bulb in the middle of the garage to begin with. I tied 3 into the existing fixture and then 3 more into a new circuit off the subpanel. The garage door opener has a motion light so that works out well if im just running into the garage for something I dont have to mess with the other lights. Ill take some pics and post them shortly.

 

[Austin_Jim]

Greatly appreciated guys. I called the electrician and asked him if he could put in a dedicated switch and rough in some spots where I will put the rows of lights. We'll see what he says.

 

[Stevie-Ray]

I am thinking 9-12 4 ft dual T8s. Thanks,
Jim

Wow, I've got a 24X48 and I have only 13 4' T8s. It's plenty of light and I haven't even drywalled yet. I think 6 would be good, 8 would be quite bright.

 

[cagullett1]

Wow, I've got a 24X48 and I have only 13 4' T8s. It's plenty of light and I haven't even drywalled yet. I think 6 would be good, 8 would be quite bright.

I have to agree with this. I was in your exact same boat just a few months ago. We bought a brand new production house with only one light. I added a switch to control my "work" lights, but I have 5, 4' T8 lights for my 20x20 garage. With lighting, a couple things should be taken into consideration with how many lights you install. Ceiling height and whether you have drywall and if it is painted or not. Those change how reflective the lighting is. Having 4 lights to work with, I have a light every 4 feet. Given my 8' ceilings and painted walls, this is plenty bright. Walking into my house afterwards makes my house look yellow.

 

[pattenp]

Sometimes we loose track of what the space is being used for when suggesting lighting, I know I do. When I suggest 100LU per sqft I'm thinking of a space that some level of detailed work is being performed. In my case my 20X20 garage is primarily used as a wood working shop so I need good light. If your garage is just being used to park the cars and store the lawn mower and weed whacker then you don't need a lot of general light, may be just some task lighting over a bench.

I have to agree with this. I was in your exact same boat just a few months ago. We bought a brand new production house with only one light. I added a switch to control my "work" lights, but I have 5, 4' T8 lights for my 20x20 garage. With lighting, a couple things should be taken into consideration with how many lights you install. Ceiling height and whether you have drywall and if it is painted or not. Those change how reflective the lighting is. Having 4 lights to work with, I have a light every 4 feet. Given my 8' ceilings and painted walls, this is plenty bright. Walking into my house afterwards makes my house look yellow.

 

[matt151617]

I have a 26x26, unfinished. I put up 6 4 ft T8 fixtures with 2 bulbs each, and another 2 fixtures over my workbench. It's pretty bright, and good enough to work on my cars. I still need a handheld light for underneath the hood and under the engine.

 

[cagullett1]

Sometimes we loose track of what the space is being used for when suggesting lighting, I know I do. When I suggest 100LU per sqft I'm thinking of a space that some level of detailed work is being performed. In my case my 20X20 garage is primarily used as a wood working shop so I need good light. If your garage is just being used to park the cars and store the lawn mower and weed whacker then you don't need a lot of general light, may be just some task lighting over a bench.

I agree. I use my garage for wood working (not professionally), and misc. car work. With the right bulbs, my garage is as bright as daylight. I will add that an extra light when working deep in an engine bay is needed.

Also, with only 5 lights, I have 2 switches. I would recommend have atleast 3 switches if you have any more lights than 5.

 

[Austin_Jim]

Thanks again guys. Just got word back from the electrician. They are wiring a switch with 9 pre-wired places for lights in my garage off its own 20A circuit. I asked for the outer rows of 3 to be 3 ft from the wall and the third down the middle. Gonna be 6 months until the house is finished, but I'll show pictures when it's done.

it may be too much light, but I'd rather have too much than not enough. I may just start with 6 of them, but since they're pre-wired, I have the option to do more.

-Jim

 

[Kevin C]

Minor correction: You near-certainly CAN

I can't swear that either of these fires were necessarily started by the vessels' DC electrical systems; but in at least the first case, it seems a distinct possibility.

Never underestimate the power of CURRENT.

Very true.... What triggered this explosion was DC current from a battery.

View media item 34107

 

[2ManyProjects]

Thanks again guys. Just got word back from the electrician. They are wiring a switch with 9 pre-wired places for lights in my garage off its own 20A circuit.

Glad to hear that you're upgrading the lighting; but I think there is still some confusion and/or miscommunication in play here...

First, presuming a total of nine twin-tube F32T8 fixtures, you simply don't need a 20A circuit to support that; 15A will be more than adequate. Upgrading that to a 20A circuit won't hurt anything; but it is at least mostly a waste and you have better places to put that (admittedly small amount of) money.

Second, what you DO want a 20A circuit for are the general-purpose 120V outlets which will presumably be scattered about the space (specific ideas on HOW to scatter them about can follow, if need be). Further, this should be a dedicated 20A circuit, NOT shared with the lighting or with any loads inside the house. And at least in your "wrenching" garage, a good argument can be made that it really ought to be TWO dedicated 20A circuits.

And finally, you do NOT want all nine fixtures on the same switch. The lighting needs to be on AT LEAST two switches ("walk-through" vs. "get to work" lights); and really, given that "3 x 3" pattern, the three-bank arrangement I suggested in Post #8 http://www.garagejournal.com/forum/showpost.php?p=3403499&postcount=8 would be near-ideal.

I asked for the outer rows of 3 to be 3 ft from the wall and the third down the middle.

I might have pushed those outer rows a bit further out (say, to two feet off the walls); but that's just a tiny nit-pick. Three feet will likely work fine.

Gonna be 6 months until the house is finished, but I'll show pictures when it's done.

It's a "Hangin' Offense", if you don't!

it may be too much light, but I'd rather have too much than not enough.

I agree completely, PROVIDED THAT:

I may just start with 6 of them, but since they're pre-wired, I have the option to do more.

This is where the multi-bank switching comes in. It gives you the ability to control how much lighting you use on an as-needed basis. And it is NOT difficult or expensive to do, as long as it's done during the initial rough-in process. So NOW is the time to get it right.

 

[Austin_Jim]

Again, thanks 2Many. I guess I didn't say that they are also leaving the 'stock' light that comes with the house on it's own switch. So we will have two sets of lights - the single walking through fluorescent and the set of 'working' lights on another switch.

 

[2ManyProjects]

Again, thanks 2Many. I guess I didn't say that they are also leaving the 'stock' light that comes with the house on it's own switch. So we will have two sets of lights - the single walking through fluorescent and the set of 'working' lights on another switch.

OK, I'll settle.

If it were my garage, I'd still do the three-bank arrangement, as previously described; but "1 + 8" will likely do what you really NEED to do.

 

[oldgoat]

I have a 22 x 26 with 7 4 ft fluorescent lights. Three down the middle and two on each side with each row on its own switch. I didn't llisten to my friend when he wired the extra outlets in since he rec that I have the switches at the door instead of one at the door and one on each side. I have mine plugged in and like that better. Maybe it doesn't look as pretty, but it does make it a lot easier to reposition the lights as you start using the garage. If it is going to be inspected then I would suspect that the constractor and inspector would question having the place pre wired for extra. Leaving the walls and ceiling open is a good idea though. Makes it much easier to make changes. Since mine is all sheetrocked and insulated I am pretty much stuck with what I have now, but it is very close to what I want so I don't have a issue.

 

[fkfw]

Hey Old Goat,

Are you using 2-bulb 4 footers on your 7 fixtures? I'm thinking of using 8, 4-bulb 8 footers in two parallel rows for a total of about 46,000 lumens (2900 per bulb x 16)

I have a 23 x 23 sheet rocked and painted white garage with a 9' to 14' sloped ceiling - and no obstructions on the ceiling.

Is this too much light or is there such a thing? It's prewired so I will have all the lights on a single switch on a 20A breaker. I need good light for welding and car and wood stuff but I'm not clear on how much is enough...

 

[2ManyProjects]

Hey Old Goat,

Are you using 2-bulb 4 footers on your 7 fixtures?

First, welcome to Garage Journal.

Second, this really should have been posted as a new thread, rather than tacked onto a month-old thread that doesn't have much in common with YOUR application. Perhaps one of the moderators can split it (and this reply, and any subsequent replies) off to a new thread?

I'm thinking of using 8, 4-bulb 8 footers in two parallel rows for a total of about 46,000 lumens (2900 per bulb x 16)

Typical "Initial Lumens" value for F32T8 tubes is more like 2,800; but this is a nit-pick, really. Far more importantly, your math is WAY off: Eight fixtures at four tubes/fixture totals 32 tubes, not 16. So your total "source lumens" is approximately 89,600.

Also, twin-tube four-foot fixtures beat four-tube eight-footers every time for installation/placement and switching flexibility.

I have a 23 x 23 sheet rocked and painted white garage with a 9' to 14' sloped ceiling - and no obstructions on the ceiling.

If the space is only 23x23, how exactly are you planning on fitting two 32-foot-long strips of lighting fixtures into that space?

Beyond that, which way does the slope run, relative to where vehicles will be parked and/or worked on? And when you say "no obstructions on the ceiling", what about your garage door opener(s) and/or tracks?

Is this too much light or is there such a thing?

At the very least, it is QUITE a lot of light. Based purely on source lumens, that's almost 170 lumens/ft.^2. The usual rule of thumb is that you want about 50 lumens/ft.^2 at working height for "casual" work, and about 100 lumens/ft.^2 (again, at working height) for fine detail work. Now granted, you'll lose SOME of that 170 lumens/ft.^2 by the time you get down to working height; but certainly not anything approaching half, and it will vary somewhat with the ceiling height (which is presumably also the mounting height for the fixtures).

It's prewired so I will have all the lights on a single switch on a 20A breaker.

That's not good at all.

The 20A breaker is fine (overkill, really; but that won't hurt anything provided that the wiring itself is up to snuff). But do you REALLY want to have to turn on what amounts to an artificial Sun (and use over 1,000 watts of power in the process) just to go fetch a screwdriver or bring in the groceries?

I need good light for welding and car and wood stuff but I'm not clear on how much is enough...

I think you need to re-think this from scratch. Start with a simple diagram of the space, showing the major features -- doors, vehicle locations, workbench & cabinet locations, any major stationary tools, etc. -- and don't forget to indicate the slope direction of the ceiling relative to all that.

Also, what other electrical loads will you (eventually) have in that space, besides lighting? You already mentioned a welder (which will require its own circuit). What about such things as table saws, joiners, planers, air compressor, dust-collection system, perhaps a plasma cutter, maybe heat and/or air conditioning... The list is potentially endless.