A few lighting questions....

[stsmike]

Hi,

I have a 30' X 30' X 14' cinder block shop. 1/3 of the shop (approx 10' X 30') is divided and has an upper level for storage. I am interested in increasing the light in the main shop space. The dividing wall is white and the floor is a light colored epoxy finish.
Currently I have 3 circuits with lighting. Once circuit has a 2 bulb T12 8' light. The second circuit has two 2 bulb T12 8' lights and the third circuit has 4 250 watt metal halide fixtures that I added. I am still unhappy with the lighting in the shop.

I live in Utah, and was at Home Depot picking up some things. I noticed a display that has 4' T8 fixtures (http://www.homedepot.com/p/Lithonia-Lighting-2-Light-Utility-Light-3348-2L32W-WRAP/100654395) for $23.87 each; but these have a $20.00 rebate for each fixture) from the power company making the total cost $2.87 each. The fixtures don't have the highest ratings, but for the price.... I also checked and there is no limit on the amount of rebates, so I can purchase as many as I want.

So, I am thinking about purchasing 30? or more of these lights to replace the existing lighting I have. 3 rows of 10 in my shop should increase the light in the shop substantially. I would utilize all 3 circuits, so that I could adjust the lighting to appropriate levels if desired.

It might be excessive, but good lighting is very important to me. Does anybody see any issues with this plan? I know the fixtures aren't the best quality, but I could purchase a few extra for that price...

Also, anybody have any recommendations for bulbs for these?

Thanks,
Mike

 

[Stuart in MN]

Lithonia has some design tools on their website where you can enter the dimensions of the room and how many footcandles you want, and it will generate a suggested layout diagram. However, they don't seem to have that feature for all their products - I looked up this light and couldn't find one. I did find a similar fixture in their contractor select line that does have the design tool available: http://www.visual-3d.com/tools/interior/default.aspx?id=42911 It may not be perfect but should give you a good idea. (edit: it may ask you to log in, but you can just click on the cancel button and move on.)

The amount of footcandles required is subjective - many people here go for 100 footcandles or more, but guidelines say anywhere from 50 to 100. Here's one reference chart: http://eeref.engr.oregonstate.edu/@api/deki/files/993/=Footcandle_Recommendations.pdf
You may want to consider having higher levels of task lighting over workbenches or machine tools.

 

[stsmike]

Thanks for the information!! I was also thinking about a few extra lights above my tool box and work bench.

Mike