# recessed lighting layout



## Chris Simms (Oct 23, 2007)

I need a little help with a lighting layout 
Room is 40 ft X 36 ft and the are wanting recessed cans.
Room is for a youth bible study area with 8 or 9 ft ceilings.
I have tried several calculators and I wanted another opinion.
I come up with 2 ft off the walls and about 4 ft apart 65 watt bulbs.
What do you think ?


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## yankeewired (Jul 3, 2008)

65 BR30 Lamps are good choice for a dwelling but I think you would want to look at a LED trim/lamp unit.Thats assuming your not working with a drop ceiling where you would almost certainly use florescent drop ins. You will eliminate maintenance and greatly reduce energy costs for the Church and most groups of folks will appreciate those savings . Of course its abit more on the install but the pay back period would be short. I would also say that 4 feet apart sounds a bit close. Determine the output and what you require per sq ft. You will need to detemine the finish ceiling height . My hunch is around four feet off the wall then 6-8 feet apart.


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## chicken steve (Mar 22, 2011)

lot of _variables_ Chris

one would be that 65W element

would that be a flood, narrow flood, long neck, shortie?

photometrics are always a beeeeatch

if i can, i'll always over illuminate, they can either dim or switch a portion off

~CS~


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## Chris Simms (Oct 23, 2007)

I will try to upsell the LEDs after I check with my supplier on the cost.
The ceiling is sheet rock 8 or 9 ft. This is a remodel but have plenty of room to wire in attic. The sites I was looking at was using 40? watt indoor floods and had good lighting at 4 ft circle and some lighting up to 9 ft
http://www.electriciantalk.com/attachment.php?attachmentid=12220&stc=1&d=1330730728


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## electricalwiz (Mar 12, 2011)

what does the "A" mean
with that layout you are going to have some mean shadows,


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## yankeewired (Jul 3, 2008)

Ecosmart made by cree @ my local Orange is $25 ea. Not much more that a full trim and indoor flood.


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## svh19044 (Jul 1, 2008)

Chris Simms said:


> I need a little help with a lighting layout
> Room is 40 ft X 36 ft and the are wanting recessed cans.
> Room is for a youth bible study area with 8 or 9 ft ceilings.
> I have tried several calculators and I wanted another opinion.
> ...


65w BR/R30's are a very poor choice for a bible study. Let's suggest somewhere in the 80-100 footcandle range, and start on the low end of 80, and assume a 6" reflector trim. 

Starting at 1.5' in, you will need them placed roughly every 3', for a total of 168 cans. 

If we go on an extreme low end of 50 footcandle, I come up with roughly every 4', for a total of 100 cans. I'm guessing that is what you based it on.

If we jump up to the 75w halogen R30 at 1020 lumens, you can cut the amount of cans down by 30 for a total of 70, placed every 4.5'. 

With roughly 100 bulbs being replaced every 2000 hours or less, who is paying for the maintenance? Now you have two options...

As noted above, an LED, probably a roughly 14w unit to get you in the 1000 lumen range. Depending on a couple variables, it's going to be similar to the 75w R30 halogen example above. Just make sure you spec the LED's correctly for this application as many have a very narrow spread.

The other option that I would look in to, and the one that I would push, is a 4pin quad fluorescent fixture with reflector for general lighting. Rated for over 10,000 hours, same price per bulb, and at 26w produces over 1700 lumens. You can place them every 5' for a total of roughly 55 cans for 50 footcandles, or every 4 to 4.5' for a total of roughly 80 cans to get to 80 footcandle.


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## B W E (May 1, 2011)

chicken steve said:


> lot of variables Chris
> 
> one would be that 65W element
> 
> ...


What does long/short neck have to do with photo metrics?


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## Honestly (Feb 3, 2011)

svh19044 said:


> 65w BR/R30's are a very poor choice for a bible study. Let's suggest somewhere in the 80-100 footcandle range, and start on the low end of 80, and assume a 6" reflector trim.
> 
> Starting at 1.5' in, you will need them placed roughly every 3', for a total of 168 cans.
> 
> ...


Are you using a computer program or a website or what to get these numbers? I could use a good reference for this type of stuff.


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## mbednarik (Oct 10, 2011)

B W E said:


> What does long/short neck have to do with photo metrics?


I don't think the neck really changes the photometrics. I think it has more to do with different trim and fixture length requirements.


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## Cletis (Aug 20, 2010)

*troffers*

I'd just do some full spectrum t-8 2 bulb troffers every 4 grids and be done. 10 year life on bulbs, 30 yr ballast


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## Southeast Power (Jan 18, 2009)

Chris Simms said:


> I need a little help with a lighting layout
> Room is 40 ft X 36 ft and the are wanting recessed cans.
> Room is for a youth bible study area with 8 or 9 ft ceilings.
> I have tried several calculators and I wanted another opinion.
> ...


Remember,
The floor and about 3/4 of the walls will be lit and the ceiling and top of the walls will be darker.
Is this the effect you want?


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## Cletis (Aug 20, 2010)

*cans*

Cans are inefficient plain and simple. Unless they just like the "look" of them. Troffers are the way to go and probably 50% less energy for what your proposing for the same and a better spread of light. No maintainance for 10 yrs min


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## SteveO. (Oct 17, 2011)

Cletis said:


> Cans are inefficient plain and simple. Unless they just like the "look" of them. Troffers are the way to go and probably 50% less energy for what your proposing for the same and a better spread of light. No maintainance for 10 yrs min


It's a drywall ceiling, and it's finished. :thumbsup:


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## Southeast Power (Jan 18, 2009)

SteveO. said:


> It's a drywall ceiling, and it's finished. :thumbsup:


One word:
Ceiling-grid Tees


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## Cletis (Aug 20, 2010)

*oh*



SteveO. said:


> It's a drywall ceiling, and it's finished. :thumbsup:


Oh. Must have missed that. In that case, I'd do 4ft 2 or 4 bulb surface mount flourescent, or second what your doing with silver trim and 23-25W Full Spectrum Flourescent bulbs, thirdly retrofit LED ($$$)


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## SteveO. (Oct 17, 2011)

jrannis said:


> One word:
> Ceiling-grid Tees


Isn't that 2 words, or 2.5? :thumbup:


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## Dennis Alwon (May 9, 2009)

Chris Simms said:


> I need a little help with a lighting layout
> Room is 40 ft X 36 ft and the are wanting recessed cans.
> Room is for a youth bible study area with 8 or 9 ft ceilings.
> I have tried several calculators and I wanted another opinion.
> ...


I usually go 3 feet off the wall and about 5' apart. It also depends on the use. If there is no insulation you can use the non IC cans and get up to 150 bulbs in them which would probably be more than you need. LED's are a great alternative but very pricey-- It will save money over time. 

I just bought an LED double flood that is about 20 watts total and it put s out about what my 2- 90 watt halogens put out. Much different color light


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## surf (Jan 17, 2012)

I normally do 3-4' off wall,and 5-6' apart.


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