Lighting Location Question

[douglee25]

Good afternoon folks. Question relating to light placement in the ceiling.

Garage details - 40'x50'x16'
Roof pitch - 4/12
Lighting will be hung around 14'

See picture of the inside of the shop. The right most bay will be taken up by a 40' RV most of the time. Overall height of RV is around 13'.

The left side will be open for equipment work area, etc.

If you look to the ceiling, the purlins are spaced approximately 5' from what I can tell. The lighting designer shows lighting placement on the 40' side at 6.7' in from the edge and then 13.3' from there (or directly in the center). The problem with those dimensions is that it puts things right in between the purlins which will obviously add complexity to the mounting. I prefer not to use unistrut and rather use cable or chain.

I'm thinking of shifting the lighting on the right side to the 2nd purlin which would get me slightly past midpoint on the RV (maybe 10' +/- from the side). Mount the middle set of lights just past halfway to the left, and finally mount the left most set at the the first purlin (about 5' in).

Would you recommend this or mounting both sets of outer lights on the first purlins and then the center set? Again, I realize the distances aren't exact, but just trying to get some advice before proceeding.

Thanks again.

Doug

 

[Platonic Solid]

The 8.6' X direction spacing criteria [SC=8.6] in the lower left is concerning. Is the IES file from the actual fixture you're using or just a selection from the menu? Typical medium distribution fixture mounted at 14' have a max (fixture center to fixture center) spacing criteria [SC] around 14'. Go over that and your lighting becomes noticeably uneven.

 

[douglee25]

The 8.6' X direction spacing criteria [SC=8.6] in the lower left is concerning. Is the IES file from the actual fixture you're using or just a selection from the menu? Typical medium distribution fixture mounted at 14' have a max (fixture center to fixture center) spacing criteria [SC] around 14'. Go over that and your lighting becomes noticeably uneven.

Good call I accidentally selected the incorrect light.

Lighting fixture - ibe 22LM MVOLT 50K

Updated first post.

SC = 17

 

[Platonic Solid]

If the RV is 13' and the lights are at 14', I'd put that set of lights on their own switch. Whether that set is 5' or 10' from the wall won't make much difference when they're facing the RV roof. The ideal scenario would be to use 16 lights in a 4x4 pattern mounting them on purlins 1,3,5,7 and put row 7 on its own switch.

 

[douglee25]

If the RV is 13' and the lights are at 14', I'd put that set of lights on their own switch. Whether that set is 5' or 10' from the wall won't make much difference when they're facing the RV roof. The ideal scenario would be to use 16 lights in a 4x4 pattern mounting them on purlins 1,3,5,7 and put row 7 on its own switch.

Well I only ordered 12

So where would you place 12? I currently have them on dimmers and each row of 4 on one switch.

 

[cybrdyke]

A 22,000 lumen fixture mounted only 1 foot above a motor home will cause some serious damage.
CD

 

[Platonic Solid]

I'd put 12 on purlins 1,3,5 (purlin 7 being the RV space). I'd put wiring and switches for purlin 7 for when you get rid of the RV or sell the property. Around 15,000 lumen medium beam spread fixtures would have been ideal for your space, but as long as you have dimmers you'll be OK.

 

[douglee25]

A 22,000 lumen fixture mounted only 1 foot above a motor home will cause some serious damage.
CD

Yep, great point. I did specify switches for each bank and dimmers so I could work on things if I pulled it out.

 

[douglee25]

I'd put 12 on purlins 1,3,5 (purlin 7 being the RV space). I'd put wiring and switches for purlin 7 for when you get rid of the RV or sell the property. Around 15,000 lumen medium beam spread fixtures would have been ideal for your space, but as long as you have dimmers you'll be OK.

I kinda like this idea. I would agree 15k lumens would be better if I was mounting 15 or 16.

Do you feel that 8 lights in that space to the left of the RV would not be sufficient alone? Or conversely do you feel that 12 lights to the left of the RV will illuminate the space where the RV sits if I were to use the work area?

 

[Platonic Solid]

"Do you feel that 8 lights in that space to the left of the RV would not be sufficient alone?"

It's OK. Assuming you're talking using purlins 1,4, thus ~ 15ft fixture spacing. Could be worse.

"Do you feel that 12 lights to the left of the RV will illuminate the space where the RV sits if I were to use the work area?"

It would, but obviously uneven compared to the rest of the space and it would be shadow prone.

 

[douglee25]

"Do you feel that 8 lights in that space to the left of the RV would not be sufficient alone?"

It's OK. Assuming you're talking using purlins 1,4, thus ~ 15ft fixture spacing. Could be worse.

"Do you feel that 12 lights to the left of the RV will illuminate the space where the RV sits if I were to use the work area?"

It would, but obviously uneven compared to the rest of the space and it would be shadow prone.

Choices, choices... Appreciate everyone's insight... Let me sit on it for a night.