Lighting Help - Flourescent

[soapii]

Been looking through countless threads here and have done research for months and finally figured I would just ask if anyone has firsthand experience.

My garage is 30' x 44' with 12' ceilings and I want a LOT of light everywhere. I also need as much ceiling room as possible so I narrowed down my selection to some 4 foot wide 6-bulb T8 high bay fixtures. I planned to do a total of 10 of them (2 rows of 5) with roughly 8.5' between them and about 4.5' from each side wall. The fixtures have a 90* light angle so there is plenty of overlap. I drew all this up in CAD and wish I could post it as it would be much easier to explain with a picture. Bulbs for the fixtures are 32 watt (6500K and 85CRI) and the fixtures have reflectors (no uplight).

What is boils down to.......is this going to be bright?? Or should I add more fixtures, or even change my fixture and bulb type?? I thought about going with T5's but damn are the expensive.

Sorry for the long winded post but would appreciate some input.

--Joe

 

[MichMan517]

Joe,
I just put in some similar lighting on a 10' ceiling, except with 5100K bulbs, about 1 watt per SF. Looks like you would be at about 1.5 watts/sf. Your ceiling are 2' higher. I am thinking of adding another 4 bulbs or so, as I think it could be a little brighter for these eyes. I would guess that your setup it would be OK, maybe add a couple well placed lights over the workbench, etc.

 

[pattenp]

Don't get confused with watt vs lumen. Watt is power consumption where lumen is the amount of light produced. I think you are needing some where in area of 1000 lux per sqft.

Check this site... http://www.engineeringtoolbox.com/light-level-rooms-d_708.html

 

[soapii]

Joe,
I just put in some similar lighting on a 10' ceiling, except with 5100K bulbs, about 1 watt per SF. Looks like you would be at about 1.5 watts/sf. Your ceiling are 2' higher. I am thinking of adding another 4 bulbs or so, as I think it could be a little brighter for these eyes. I would guess that your setup it would be OK, maybe add a couple well placed lights over the workbench, etc.

I appreciate your input, I also see you are in SE MI, as am I. Maybe I could swing by to get an idea of the light for comparison.

--Joe

 

[soapii]

Don't get confused with watt vs lumen. Watt is power consumption where lumen is the amount of light produced. I think you are needing some where in area of 1000 lux per sqft.

Good thought. Each bulb is rated at 2,750 lumens, so 16,500 per fixture. That would be a total of 125 lumens/sft. That number means nothing to me but might to other hopefully.

Your recommendation of 1,000 lumen/sft would result in a TON of fixtures. Are you sure you don't mean 100 lumen/sft??

EDIT.....looks like you meant 1,000 lumen/sqm. Reworking my numbers yields 1,350 lumen/sqm for my application.

--Joe

 

[pattenp]

You are right... that's per sq meter. I miss read the chart. You'd get a sun tan with 1000 per sqft.

 

[MichMan517]

That would be fine Joe. I'm a short drive from Cabela's. Shoot me a PM. Serge.

 

[boros40]

I just replaced 12 2 bulb 4ft florestants with just 4 of these fixtures. It is twice the lighting and less energy. I bought them a home depot for about 80 each. Here is the link.
http://www.homedepot.com/Lighting-F...splay?langId=-1&storeId=10051&catalogId=10053

 

[Piper]

I've heard the watt vs lumen argument so I'm not going to comment on that. When I installed my florescents I used the 1.5 watts per sq foot. The garage is 31 x 23 with 11 foot ceilings, and the fixtures are open bulb with reflectors, 4' long each. Anyway, my point for posting here is that your eyesight isn't going to get any better, so if you're going to err, err on the side of too much light. When I did my calculation I don't recall how many fixtures it meant but in the end I added about 4 extras I think which helped with the look of the fixtures on the ceiling and eased the wiring from one run to another.

when I did my lighting layout I thought I was gonna feel like I was in a surgery suite but honestly it worked out great. Within reason, more is better.

 

[Lakeozark]

For a point of reference - I installed these yesterday.
They are from contractorlighting.com and are the 32W T8's as well.
Shop is 27X36 with 12' ceilings and it is plenty of light. There are 12 units (4 bulbs each at 8' long)
As a sidenote - these pics were taken shortly after they were turned on for the 1st time.
Since they were brand new, it took some time for the gases, etc to distribute and now it is actually brighter now that they have "broken in" so to speak.
You can never have too much light in my opinion.
This is appx 1.59 +/- Watts per sq. ft. to give you an idea.
Always buy the best bulbs you can afford with good lumens and good color. You wont be sorry.

 

[Falcon67]

>Shop is 27X36 with 12' ceilings and it is plenty of light. There are 12 units (4 bulbs each at 8' long)

guessing - 8' row spacing, 3 to a row, 4' between lights, 2' from wall at end of each row?