Sactuary Lighting Revamp - I need some input!

[_shorty_]

Hey everyone. Sorry in advance for the length of this, I want to be thorough. I am planning to replace all of the lighting in our small church sanctuary and I wanted to bounce my thoughts off of people with experience before I pull the trigger on purchasing anything.

 

Currently, we have 9 old pendant style fixtures. The room is ~40 x ~50 not including the stage (I'm not dealing with stage yet). There is a peak down the center of the room at (I'd guess) about 12ft tall, down to probably 8ft on the edges. The three 'largest' pendants are down the center peak, and three pendants are centered on each of the ceiling sections, spaced out evenly along the length of the room.

 

Total current calculated lumens is ~26,400 based off of the bulbs in place now. Although - being pendant style, most of the bulbs are on their side so it would seem quite a bit of that lighting energy is facing UP and hitting the ceiling which I would assume does very little for the amount of light or footcandles at each seat. It's NOT super bright in there currently with lights on full, but no-one complains.

People need to be able to read comfortably in there, and I think that is accomplished now - although I doubt more light would hurt. We can always dim them back if a lower light level is needed. So, my goal is to get too many lumens in the room vs too little.

 

My plan:

1) pull out all of the old fixtures

2) replace those 3 pendants down the peak with ceiling fans (with lights in them).

3) replace the other 6 pendants (3 along the center of each ceiling section) with LED down-lighting. I was thinking of using inexpensive LED down-lighting @15W, 18W, or 21W to do this.

4) fill in the rest of each ceiling with matching LED down-lighting to gain the desired amount of light in the room. I'm looking at 'puck' style fixtures that clamp up into a hole in the drywall and are basically flush with the ceiling. They'll be dimmable and I was looking at 'natural' lighting, which is supposed to be about 4000K-4500K. They also report a 160 degree 'beam' angle. 12W outputs ~700LM, 15W outputs average ~850LM, 18W outputs average ~1000LM, and 21W outputs average of ~1200LM.

5) Additionally - I was planning to add in DMX control via DMX dimmers to run each of my circuits (except my fans). This will be amazing - as I plan to eliminate a huge MESS of nasty wall dimmers in the back by the sound booth, and the ability to set scenes and slow transition will be awesome.

 

Several Questions:

1) Am I correct in considering that some of the current lumens are 'wasted' with the current pendant style lighting? Any idea of what percentage may be 'wasted'?

2) I've read that 20-40 footcandles provides comfortable reading levels. According to a calculator I found, our square footage would require approximately 25,800 lumens to acheive 40 footcandles, and 32,280 to achieve 50 footcandles. (I have no idea how accurate that is) Does this sound right? How many lumens and/or ft-candles would you shoot for in my position?

3) Does the LED color sound right? Currently, I'm sure we're more used to the warm white/3000K range... DO you think the 'natural' light will be too different and cause distraction?

4) How BIG of an LED fixture is too big in your opinion? The 12, 15, 18, and 21W fixtures are 5.9", 6.7", 7.7", and almost 9" respectively. I'm thinking 9" would look funny? Would 7.7"? 6.7" is probalby pretty close to a typical 6" can light.

5) I have a couple patterns I like laid out for the downlighting. I think my favorite provides about 27 downlight fixtures and if using 18W fixtures, this provides a total of about 27,000 lumens. So this is somewhere between 40 and 50 ft-candles?. The other pattern I considered using smaller fixtures more closely spaced and totals 35 fixtures. 12W, 5.9" = ~24,500 LM, and 15W, 6.7" = 29,750LM. I like the idea of the smaller 12W fixtures, but I'm not sure that the output is large enough.. as this would put us under 40 ft-candles if #2 above is correct. Any thoughts here on what would look best? and again how much output is sufficient in your opinion?

6) Anyone had any experience with these chinese made dimmable driver LED down-lights? How well do they dim? The seller says they dim 0-100%, so I'm assuming the drivers have to be outputting PWM. Any opinions here?

7) anything I'm not considering here that I should be concerned with?

 

Thanks so much if you've read all this. I appreciate any input possible!

 

[_shorty_]

UGH.. I made STUPID factor of 10 math error. Sorry! I need to re-figure everything.... .

 

Okay, I'm an idiot.

Corrections to questions above:

2) calculations - of footcandles currently @26,400 lumens is like 16.5 ft-candles. I would have guessed it's on the low side of 'reader-friendly'. This makes more sense. ALSO - I was rounding my square footage up to 2000, because of the favorable numbers, but it's really probably closer 40 x 40, or 1600ft2. So 20 ft-candles = 32,000 lumens. That sound better?

5) so based off better ft-candle calcs - the 27 x 18W fixtures provide 27,000 lumens = 16.8 (better than now but probably not good enough?). 21W fixtures with this setup would be 32,400 LM = 20.25 ft-candles which I'm guessing we'd be happy with, but are the almost 9" fixtures going to look funny? For the second layout with 35 fixtures - it would seem 15W = 29,750LM = 18.6 ft-candles. Almost there. Is this enough? Or - the 18W fixtures @7.7" each x 35 would be 35,000LM = 21.875 which would probably be more than enough, considering what we have now. But 7.7" seems large to be spaced that closely. Maybe it'd be okay.

 

Any help is much appreciated. Sorry for any confusion!!