Advice on how many light fixtures

[Wakesurfer]

I am planning the lighting for my 30' wide x 45' deep workshop. It will be used as a storage and maintenance workshop. It will be finished and the ceilings are scissor trusses with a 10' flat section in the center (yielding 16' ceiling height in the center pitching to 11' on the sides) I am planning on using 8' , four bulb T8 fluorescent fixtures. I was thinking of running 5 down the center section mounted parallel to the door and then 6 PER SIDE mounted on the pitched ceiling also parallel to the door. The fixtures I was planning on using have four 4' T8 bulbs per fixture (up to 32W each for a total of 128W per fixture). I was going to split them into four switches to allow individual sections to be lit as necessary.

My question is; is this enough, too much or just the right amount of light. My goal is to have a workshop with very good light for (primarily) car/boat maintenance, but not something that requires sunglasses and SPF50 sunblock!
TIA

 

[rdsk8ter]

add about 10% more lighting then you think you need and put them on separate switches. What color spectrum lightning are you running? I would run for the 850 series. sounds like you have a fairly good layout in mind but sketch it up really quick and it will help visualize it.

 

[Thumper68]

Add the extra lights now, it's a pita to add more later, don't ask how I know this.

I would avoid putting them directly over the main works area, odds are that you won't be working on the roof of a vehicle. I just moved some of mine to the sides so I can see where i'm working without having to use aux lighting.

 

[Steevo]

So, 17 total fixtures for your 30 x 45 space?

That is how many I used for my 24 x 40 shop.
I ran mine in rows, approx 6' apart, down the long direction of my ceiling.
It sounds like you'd be placing yours across the short direction, and spacing them at about 6.5 feet apart on the angled sides and 7.5 feet apart on the flat center part.
That should be a decent amount of light, but the incremental cost of adding some now would save you the trouble of adding later or dealing with dim areas.
The ends would be less bright, since your first fixture is seven feet or so from the end wall, whereas the rest of the shop has coverage from two directions, and no more than 3.5 feet of horizontal distance to the nearest one.
Why not use the same number in the center as the sides? That adds one fixture, and then adding another row would take three more, for a total of 21.
You'd then be at seven per ceiling plane, and could easily run seven per switch.

 

[regguy1]

I agree with Steevo, not enough for that space

I have 20 48" 2 tube T8's with 6500K tubes in a 26' x 30' see photos and videos here:

http://www.garagejournal.com/forum/showthread.php?t=140674&highlight=26'+30'+Garage+photos+videos

It's quite bright in there, the videos look somewhat darker because they were done with a digital camera

You can see a toolbox review done in there the brightness is about right in that video:

 

[motormitch]

I have a 4000sqft shop with 36 (6) tube fixtures. (high bay T8) and I usually run 50-75% of them for most projects, but 100% when I need really good lighting. I love it.

 

[pattenp]

Typical T8 tube output is 2800 lumens. A 150 lumens per sqft is considered very good light. So 1350SF X 150LU = 202500 LU. 202500LU / 2800LU = 72 lamps or 18 4 lamp fixtures.

 

[Wakesurfer]

Thanks for all of the responses! This forum is fantastic! I will increase the number of fixtures and put in a few spare boxes with covers for possible future use as Thumper suggested. Steevo, I think I will go with a configuration similar to what you suggested. Thanks again.