What lights can do the job?

[jives]

Hi all:
The picture below shows our garage plan. 14' walls, vaulted ceiling with a
6:12 pitch interior. Move out the cars, play basketball. Ideally, we would like
a single row of lights down the center that could light up the place. The peak
is at just about 20'. Putting a single row there would put fewer lights in
harms way from balls. It would also mean the garage doors when open would
not be in the way. The last thing we want are 20+ flourescent strip lights
scattered over the ceiling.

The ceiling will be white steel, insulated. Walls painted light. I've been
looking at LED (WOW! the cost!), low bay flourescent tubes (8 light fixtures
with high luman output), and HID (metal halide). The light will need to flood
the walls and floor. I've talked to some folks, and read as much about
photometric charts as I can. Now, do any of you have experience with this
sort of thing? What kind of light fixture could satisfy these requirements?

Metal halide are cheap to come by used. But, they are big and may be low
hanging fruit for balls.

Another alternative is two rows on either side of the peak, aiming either
down or at an angle. Thoughts?

Separate task lighting can go in the workshop area.

 

[Mustang51js]

Price wise you would be looking at metal halide for the best lighting up that high.

 

[CJCar]

I'd do two rows of 4 (6) lamp T5 fluorescent high bays. You can get protective wire cages for them. Should put you close to 50 foot candles at 30" above the floor. PM me and I can do a photometric layout for you tomorrow.

 

[Charles (in GA)]

T5HO lighting is the way to go.

This is NICE.

More pics by this member can be found HERE, which is a post in THIS THREAD.

Protective wire cages are available for most commercial and industrial fixtures. "Mandatory" in gyms.

Charles

 

[jives]

Wow, Charles, I never even thought about hanging the lights below the garage door
tracks! We will also have the tracks follow the roof pitch. And yes, the fixtures will
have wraps or wire cages.

CJCar -- I have sent a PM.

Jeff

 

[CJCar]

Here's two quick layouts, both with six T5HO fixtures at 16', one with 4 lamps, the other with 6 lamps. I used International Lighting Products IES files just because I had them handy - and we've installed thousands of them. These are basic fixtures and any manufacturer should have something equivalent.

Here's a link the to ILP fixtures: http://www.ilp-inc.com/FLU-Himalayan3.html

For reference, fc stands for foot candles, 1fc is equal to the light one candle will emit on a flat surface 1 foot away. Your average office space is usually around 50fc.

The 4 lamp fixtures give an average of 57fc, and the 6 lamp fixtures give 87fc.

 

[cybrdyke]

Good job CJCar. I cant do point x points from home, or I would have done it.

Just so that some of you know....more foot candles isn't necessarily better. Like the 6 lamp layout above that averages 87 fc. That's way over the top.

 

[CJCar]

Good job CJCar. I cant do point x points from home, or I would have done it.

Just so that some of you know....more foot candles isn't necessarily better. Like the 6 lamp layout above that averages 87 fc. That's way over the top.

Thanks! I will have over 100fc at the floor in my shop with T8 HO. Over the top? I don't think so if it's switched properly - I can adjust the light level to the task at hand.

 

[jives]

This is why I love GJ! Thanks gents, I've now got a plan with fewer fixtures than I had
anticipated. As for the fc levels, I like it bright, and my eyes ain't what they used to be.

Out of curiosity, do you think 3 or 4 typical low bay 400W HID metal halides with about
30,000 lumen each, hung right down the middle under the peak, would do the job? I ask
this because I think I can get 4 or 5 of the for about $20 each, working condition, with
bulbs.

Jeff

 

[Charles (in GA)]

No they won't. The fc will vary greatly depending on the exact fixture and the age of the bulb, but using a Lithonia TX400MP PA22C which is a 400 watt MH with a acrylic reflector and conical lens producing about 44,000 lumen new, four down the middle will yield only about 60 fc at 2½ ft off the floor. The sides will most certainly be dark.

With another style with a aluminum reflector designed for wide light dispersion and a dropped lens, 42,000 lumen, I get 64 fc at the 2½ ft work height.

Just isn't going to happen. Expect used fixtures to be about ¾ or less of the light output of the new ones, depending on condition and bulb age.

Charles

 

[jives]

Yeah, that is what I suspected, particularly with the used metal halide lights and their failing light output with age. I guess that is why they are so cheap used. . .

Great info, great help, so very appreciative.

Jeff