Need help on estimating shop lighting requirements

[dstig1]

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[ETpilot]

I've used them on commercial jobs. They are efficient, very good lighting, but the down side is you really need a lot of ceiling height to get even light distribution, I haven't seen long ballast life, and they are staggeringly expensive.

I did some research on these lights before deciding on them. I did read about the ceiling height issue but was more interested in getting lumen output close to what I had. T5 came close. I installed it centered in shop parallel to long wall. Brightness is good and I don't see a problem with ceiling height. The fixture does not have a reflector so I am going to add one and see how that does. I am satisfied. Cold starts are not a problem but it was a problem with my old fixture. My old fixture, about 30 years, is industrial so the height requirement may have applied too.

 

[BitChin1]

The most cost effective way to wire is EMT use 10' lengths to separate lampholders, use 165 Raco or equivalent. Arlington 800 and 370. Get ground screws. place the boxes in an E pattern, I would run down the front wall above the door where doors won't hit it and lights won't burn the ceiling. I'm guessing a two bay, 3 boxes each side of overhead doors. Bend Emt to fit to ceiling, run with 10' or shorten to gain one more light in each bay, With 9 or 12 boxes. Use Leviton 29816 C2 porcelain sockets with pull chains. #14 solid THHN three conductors (black white green). Ideal 341 wire nut, use a solid tail #14 12" long to connect each color together Use ground screws (special for the purpose) to ground each green to the box. Strip 5/8" on each, don't be lazy, twist until you see two full spirals of each conductor outside the wire nut. After mounting fixtures on boxes, staple one end of a 8" piece of light chain to the ceiling about 14" away from box. Run pull string through other end before connecting to fixture. Home Depot sells a (compact fluorescent) 68 watts (replacement for 300 watt incandescent)
Power all of this through a switch on the wall. Use the pull strings to turn off unneeded bulbs.

Happen to have any pics of this type install? I too am getting ready to start a garage project and am estimating electrical cost this weekend - I like this approach

 

[scott_vt]

Whats the best way to estimate shop light requirements? A few years ago I built a 24 x 26 garage with a 10' ceiling. The interior walls and the ceiling are finished with standard unpainted OSB and the concrete floor is painted white (you would be amazed how much that helps lighten up the inside of the building). I finally got around to running 100 amp service to the building and I will be using conduit and boxes to run all the wiring. I am tryng to determine what type of light fixtures would work best in this appliation and how many fixtures I will need. I prefer a brightly lit building interior over a dimly lit building interior. Would appreciate some opinions. Thanks.

Good Mornin jeepcj7,
Back in 2010 I built a 28 by 44 barn, partitioned so that my shop section is about 19 by 27 inside dimension. I also have 10 ft ceilings and the floor also concrete, I have not painted my floor. Ceiling and walls are sheetrock in that section of the barn and painted off white. I use 4 T-8 fixtures, four bulbs each fixture, and they really light that shop up ! Like you stated the white makes a big difference. I would think that the only additional light you might need would be a bench light for some very intricate work JMO .....

 

[pinetree10]

Not sure if you're still looking for input or not but I have a very similar garage, 24 x 24, plywood walls painted a sort of light beige/army green and bare concrete floor which is the typical light gray. There's no ceiling so I just hung four 8-foot, 4-tube T8 fixtures off the horizontal lumber 11 feet from the floor, in the center of the space from side to side and evenly spaced front to back. The 16 tubes are 32 watts each so that's 512 watts for 576 square feet.

It's not lit up like a body shop but I've found the electronic ballasts to be very quiet, quick starting in the extreme cold (single digits and lower lately), and plenty bright once they've had a chance to warm up for a few minutes in these temperatures. I also have a separate four footer over my workbench in the corner but other than that I've found that the arrangement provides adequate light for the work I do. If you're a lot more picky about dark areas and ensuring every corner is bright I would go with the industry's formulas instead of going on experience like I did. I used to work for an electrician and I bought and installed everything based on the jobs we did over the years.

It sounds like you're doing it right with the big service and the conduit. Post some pictures when you're done if possible. Everybody likes to see the final product. Good luck.

 

[frhrwa]

I installed and repaired all of the 8' double tube units in a friends upholstery shop, they worked great.. but.... when we went to Home Depot to get a couple of ballasts, the display had some lights that used a small diameter tube and they were over twice as bright.. newer technology.. I reommend checking them out, can't remember which units, but when you look at the display, you'll find them easily, they are so bright you won't stare at them and they outshine the others by a mile..

 

[George2615]

My original garage I built is similar to yours. It's 24 x24 with 14' ceiling. Built it high because I have a two post car lift. For lighting I originally used 4' 2 tube T12 fixtures but after many years and T12 tubes not being made anymore I replaced them with 4' 2 tube T8 fixtures. I have 8 total. 6 are suspended down 4' on chains and 2 are mounted to a side wall. Then I added an 18 x 32 addition on the back of the garage. In there I used 2 rows of 4' T8 fixtures also hanging on chains (8 total) and one more over a work bench. All the T8 fixtures I used say for cold start use. The main garage is not heated unless I need to work in there. Then I use a kerosene salamander for heat. The back addition has a mobile home oil furnace for heat. I have that set for 45 degrees and bump it up to 60 if I need to work out there.

 

[Willie B]

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Yup, but I'm usually right. I was told this was a Ben Franklyn quote, but I can't find it. Until now I claimed it as my own,and got away with it.

 

[grsthegreat]

I installed and repaired all of the 8' double tube units in a friends upholstery shop, they worked great.. but.... when we went to Home Depot to get a couple of ballasts, the display had some lights that used a small diameter tube and they were over twice as bright.. newer technology.. I reommend checking them out, can't remember which units, but when you look at the display, you'll find them easily, they are so bright you won't stare at them and they outshine the others by a mile..

the small diameter tubes are the t5's.

the best t5 are the 54 watt variety. but the problem is if you have a 6 lamp t5 your looking at 300 watts power use. so you dont want to go crazy with them. They also work best when there set above 15'.

 

[Willie B]

the small diameter tubes are the t5's.

the best t5 are the 54 watt variety. but the problem is if you have a 6 lamp t5 your looking at 300 watts power use. so you dont want to go crazy with them. They also work best when there set above 15'.

Be careful, there are some 27 watt T5 fixtures at Home Depot, They don't throw a lot of light, don't light well in cold, bulb and ballast life are short, I can't find replacement ballasts from usual sources.
Although HO 54 Watt T5,(5/8") are the future of fluorescent, they will soon be eclipsed by LEDs consuming less than half the power. Even very high quality HO T5 fixtures seem to have short ballast life.
For a small fraction of the cost you can have Leviton 29816-C2 porcelain sockets with CFL 68 watt (300 watt equivalent) from Home Depot. These will give better light distribution, energy efficiency, (a light not needed need not be on)

 

[pinetree10]

I bought all of my 8-footers from a local commercial electrical supply business and I haven't had any problems with them. I've never really looked into it but I wonder if the product they stock is typically of a higher quality than what's often found at the big box stores. I'm sure some things are identical but I would imagine that's not always the case.

 

[Willie B]

Commonly box store fixtures will look identical to electrical supply fixtures. In fluorescent fixtures, the difference is often the ballast. My experience is mostly Home Depot, the part number may be the same as wholesaler, or an extra digit, the ballast is typically smaller, fussier, less efficient, with short life span. In my living room,(cathedral ceiling), I have on the vertical wall at 9' a 12" wide shelf, a model tractor collection is displayed, a 3" wide board on edge is parallel to the wall 3" away from the wall. Concealed behind it are fluorescent strip lights facing up, indirect, it uses the ceiling as a reflector. I bought 14 4' strip lights from Home Depot. They were Lithonia, the same model# as I have used for years. One by one they failed. Using bigger, appropriate replacement ballasts the light got brighter. This random difference bothered me. I ended up replacing them all. So much for the savings.

A tool rep. for one of the major brand name power tool companies had a similar story. Quality control weeds them out. Flawless tools go one way, the others go to box stores.

 

[ETpilot]

I purchased a 65W CFL light just to check it out. I was not impressed with the light. I wanted bright daylight type light. The T5 54W HO light was the answer. Yes, more watts used. But, by comparing to my old fixture the difference was night and day . My old fixture was a 2 bulb fluorescent 27,000 lumens at 428W. This was really bright for me. With the new T5 I get 20,000 lumen at 216W. With 2 fixtures I will have 40,000 lumen at 432W. Long term I am saving in this deal for more light. I don' turn them on all the time as I have 2 overhead doors opposite each other. It will be interesting to see what 40,000 lumens looks like when I get the second fixture and add the reflectors.

If you want daylight type light, look at the T5 HO. Just my opinion. The ceiling height issue is a non-issue for me.

 

[Willie B]

I purchased a 65W CFL light just to check it out. I was not impressed with the light. I wanted bright daylight type light. The T5 54W HO light was the answer. Yes, more watts used. But, by comparing to my old fixture the difference was night and day . My old fixture was a 2 bulb fluorescent 27,000 lumens at 428W. This was really bright for me. With the new T5 I get 20,000 lumen at 216W. With 2 fixtures I will have 40,000 lumen at 432W. Long term I am saving in this deal for more light. I don' turn them on all the time as I have 2 overhead doors opposite each other. It will be interesting to see what 40,000 lumens looks like when I get the second fixture and add the reflectors.

If you want daylight type light, look at the T5 HO. Just my opinion. The ceiling height issue is a non-issue for me.

Don't forget ballast wattage in your numbers. I love them too. I get them wholesale, but can't afford them, In my garage, color temperature, and color rendering is secondary to even light distribution. The best lighting is two lights, one over each shoulder. If I could predict where my shoulders will be, two lights is all I would need. Having multiple lights each with pull strings, controlled by a master switch gives me the ability to turn on lights I need.The others not turned on, save energy.

 

[OldMasterTech]

Mine is almost the same size, 28 x 30. I ran 3 rows of T8s, each row on it's own switch, for a total of 36 bulbs = daytime!

 

[Steve_Miller]

I've got a little less than a watt per square foot using six 4' X 4 lamp, T8, 6500K flourescent fixtures. Happy with the light levels. Age will/does require more light in my case.

Steve

 

[robstaples]

There are programs to calculate your lumen requirement. This below link is interactive and free. You model your building (rectangular only) and pick a fixture and bulb output and the foot candles and it calculates the number and location for even distribution. You can try different fixtures and bulb ( like HO for High output) I used this in my shop and decided on 96" twin HO every 15'
Visual
You can determine your foot candles from the insert
View attachment 357449