Lighting for a Sloped Ceiling

[72Anthony]

Looking for input on a sloped ceiling.

Interior dimensions are 20' x 30', and the ceiling height goes from 11'-6" to 14'-8" (12-2 pitch). Do any of the online calculators account for a sloped ceiling, as I'd prefer to mount them directly to the ceiling and not suspend them.

In my last two garages (8' and 9' ceilings) I've used arrays of the 8ft tandem fluorescent strip lights (4 bulb T8, 32 watt) available from Home Depot. I've used the Phillips Deluxe Daylihgt bulbs with 2,600 lumens, 90 CRI, and 6,500 K.

Most of the LED fixtures I've seen were not hardwired. I did take a quick look at Grainger and their 4' fixtures were in the $160 range.

 

[cybrdyke]

4' LED tubes in non-ballasted strips is an option. The strips are hardwired. You can get the tubes with rotatable ends so that even though the strip is at an angle, the tubes can point straight down.
Just one option...
CD

 

[Platonic Solid]

Looking for input on a sloped ceiling.

Interior dimensions are 20' x 30', and the ceiling height goes from 11'-6" to 14'-8" (12-2 pitch). Do any of the online calculators account for a sloped ceiling, as I'd prefer to mount them directly to the ceiling and not suspend them.

I haven't seen any online layout program that permits sloped ceiling input. Dialux Evo (link) is good for this once you get past the learning curve.

 

[72Anthony]

4' LED tubes in non-ballasted strips is an option. The strips are hardwired. You can get the tubes with rotatable ends so that even though the strip is at an angle, the tubes can point straight down.
Just one option...
CD

Thanks for the info. Could you link to an example? So they sell strip fixtures without ballasts and then you use LED tubes?

 

[Platonic Solid]

Thanks for the info. Could you link to an example? So they sell strip fixtures without ballasts and then you use LED tubes?

See post #1 in best light fixture sticky (link in sig below). Rotating ends may be harder to find.

 

[cleanspg]

I have a similar setup. At the end of the day, your 12-2 slope isn't going to matter a whole lot. You will point the light into the center a little more, but the lights in the center are going to be higher up.

Take the average height and run your calculations. You will have better planned and executed lighting than any shop you've likely ever been in before.

Or assuming this is an open rectangle with nothing else weird about it, just follow all the base principals discussed in the stickied lighting threads and find a couple of similar examples that Platonic Solid has run for others and you will likely be happy.
Surround your work area with lights (around the cars, not on top), keep the lights far enough off the walls to not be blocked by whatever shelves you end up using and add as many as is realistic and affordable. Don't use highbay lights unless you have high ceilings, frosted lenses for less glare, etc.

I have a 24x32 with an interior slope of 3-12 on the 32 ft length. I used a total of 40 4ft led tubes, some in the maxlight fixtures from the best lighting thread and some in 8ft fixtures that I found on craigslist. About half the lights are 5000K leds from the same thread and the other half are a mixture of phillips flourescent and led replacements using the ballasts. (got a deal on those).

I love the lighting. Almost no shadows and the only place where task lighting is necessary is under a car on the lift. The glare from the lights is not bothersome even looking up. I have three rows of 8 bulbs in the 32ft dimension. 1 row of 8 over the workbench at the back. You can see shadows under the cabinets, but they don't reach the bench. 2 each at the front and back of the main lift work area and a bonus 4 at the peak which lights things up a bit better when non car work is being done. Assuming I bought everything new it would be about $600 worth of bulbs and fixtures.

Here it is with only 12 bulbs lit up. Its not 100% symmetrical as I avoided extra blocking and the lights follow the joist the best matched the position I was looking for.
Its not perfect, I reused calculations done for similar layouts and adjusted to fit the physical layout, but at the end of the day its the best lit shop I have ever been in. After the lift, the lighting is the first thing anyone visiting mentions.