wow thanks for the detailed response really helped out
.
You're welcome.
by any chance you don't happen to have the lighting you recommended do you?
No. They would be highly inappropriate for my typical-tract-house 2-car garage with its ~10-foot ceiling.
I really like to see what the light given off by them looks like. I don't know a whole lot on lighting so I just really going off of what im told. im going to be installing these my self so I am open for any suggestions.
Fluorescent tubes are fluorescent tubes. The fixture itself (and the way it is installed) will determine the lighting pattern & coverage, and secondarily influence the overall brightness down at working height; but in general, the only thing that will significantly influence the QUALITY of the light is the Color Temperature and CRI of whatever tubes you install. That is an important (if somewhat personal) choice in terms of being happy with the final result, but it doesn't really have much/any impact on the number & type of fixtures you need in a given space.
One tip in the DIY vein, tho' you're not really "there" yet: When you do settle on a type of fixture and a basic layout, make sure to figure on wiring them up in
AT LEAST three separately switched banks (probably even more than this, considering the large space). One switch loop (with physical switches located at EVERY possible entrance point) should operate your "walk-through" lighting -- a very minimal number (perhaps a half-dozen or so, but it depends somewhat on the layout) of fixtures distributed throughout the space, whose sole purpose is to keep you from tripping over stuff as you initially enter the building and maneuver through it (such as to grab a tool or other "short term" need). The rest of the lights should be broken up into at least two banks (or two banks "per zone", if you are also doing zoning -- which in that size space, is probably also worthwhile) on a "more or less every other fixture" basis, so that you can control the
intensity of the light produced at any given moment. If these two banks are somewhat unequal in terms of the tube/fixture count, so much the better; that will give you that much more flexibility. Another way to accomplish essentially the same thing is to use fixtures with two ballasts each, so that you can operate half of the tubes in each fixture independently of the other half. Understand: Charles' (and my) recommendation for at least 100 lumens/ft.^2 at working height is definitely valid; but you won't ALWAYS need this level of illumination. So when you're only doing (let's call it) "casual" work, you don't need to be single-handedly funding your local PoCo's annual dividend. In the long run, this will save you WAY more money than either "cheaping-out" on the fixtures/tubes or using too few of them.
Visual shows 35 fixtures in a 5 x 7 row pattern to give 104 fc. This is for a 40x90x16 with a reflectance of 75% ceiling/50% walls/20% floor, using the photometrics for a IBH 12L.
That sounds about right -- EXCEPT for the 75% ceiling reflectance. I don't think he can count on anything like that.
As usual Home Depot gives a Lithonia number that Lithonia does not show on their site. However the specs on the 11L and 12L appear to be the same or very close.
I did find the 11L specs on Lithonia's site at one point, but can't lay my hands on the URL at the moment. In any event, you are correct: They're close, but not QUITE the same. The 12L is rated at 12,000 lumens; the 11L at 11,000 (Home Despot says 11,200). So within 10% in any event.
100 fc at a 2 ft working height is pretty standard. I cannot imagine having much less if you intend to do work in the building.
I largely agree.
Get some T5HO strips and install them. Fancy fixtures cost money.
I would be very leery of simple open-strip fixtures in an application such as the OP's. I'm guessing this is an open-truss situation; so without any reflectors, much of the tubes' output would be wasted lighting up the underside of the roof, without much/any "gain" (at more useful heights) from ceiling reflectance.
If you want more than the strips, get the I beam fixtures from Lithonia. It will take, with 4 bulb fixtures, anywhere from 21 to 45 fixtures depending on which one is chosen. Uplighting, and wide light dispersion requires more, while narrow light distribution and no up light takes the least, to achieve 95 to 105 fc at a two foot working height.
Not to disparage Lithonia's products; but they seem a bit pricey for what they do. A quick Google check on the IBZ-454L (4-tube F54T5HO version) shows them mostly selling for ~$240-275 each. One outfit (ZORO Tools) is asking $142; but that seems suspiciously like an outlier in light of the others.
Similarly, I don't make any particular claims for that fixture from 1000bulbs.com I cited (I picked it simply as an example of the genre); but under $100 including the tubes seems a LOT more reasonable to me.
Current crop of LEDs isn't going to come close to this.
Very much agree with you on that one.
Probably the cheapest alternative is 26 of the Lithonia 4 bulb strips T5HO (two and two in tandem), common open strip. No reflector, etc. $70 at Home Depot. Visual program shows it will take about 26 of them in four rows to achieve 99 fc. $1800 worth of fixtures,
Again, the problem here is lack of ceiling reflectance. Run that "Visual" calculation again, but using something less than 10% for that value, and see how many open-strip fixtures he'd need. For the ~20% extra the ones I cited cost, they would surely produce a LOT more light (half-again? maybe closer to double?) down at working height. Seems like a no-brainer, to me.
Less than $2500 will get you the same light (T5HO) as $7000 will get you with the LEDs and less fixtures to wire also.
Exactly!
Most Home Depots currently have the 4 bulb T5HO tandem open strip and also the 4 bulb T5HO I beam fixture, both on display in the lighting section lit up. I have seen them in several of the Atlanta area stores. I have to assume the displays are pretty similar in all stores.
Probably so. But as I've said before, attempting to make light-quality judgements -- or worse, brightness judgements -- from typical in-store displays is HIGHLY problematic, at best.
