Replies

1. 
   Ken_Watkins | Nov 24, 2001 11:10pm | #1

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   I generally shoot for 4-5 ft on center and about 2-3 ft from each wall in 8' ceilings.

1. 
   piffin_ | Nov 25, 2001 03:35am | #2

   *I've done as close as 42" OC

1. 
   p_m | Nov 25, 2001 04:23am | #3

   *Rich, Do you wish to illuminate the room or are you willing to cave in to braindead designers? Can lights [recessed lights] have little to do with illumination. They are for decorative purposes only. Consider the geometry: you're placing the center of illumination [the filament] about 6-8"s above the ceiling plane and casting the light down thru a 6" hole. The only thing you will light up is a circle on the carpet. If the carpet [or wood floor] is dark, it will absorb most of those lumens. If it is white, it will show all your muddy footprints. Get you a florescent luminaire or maybe a chandelier. If crimpted in the billfold, a Home Depot 99c keyless lampholder with one 100 watt bulb would probably give you more luxes than 6 of your can lights. As for a formula, I can give you a formula, but it won't make any sense. What you want is a specific number of photons hitting a desired surface at a given moment. You need more for reading fine print and less to avoid tripping over children's toys. EffectiveLight = Emitted light divided by the cube root of the distance times the Correction Factor. The "Correction Factor" is whatever it takes to make the equation work out. In enginering textbooks, it is often labeled a "co-effecient". -Peter

1. 
   Alan_Kim | Nov 25, 2001 06:19am | #4

   *After going gung ho on all sorts of fancy lighting schemes and at the same time reading up on attic insulaton and venting threads at Breaktime, I decided not to punch any holes in the ceiling for any recessed lights.Been buying dimmable flourescent torch lamps for bouncing off our pure white walls and ceilings.The quality of light is excellent and they are very convenient.They consume only around 50 watts and claim to put out about 300 watt equivalent. (maybe not, but plenty bright enough for us.)These lamps are excellent during the summer because they don't crank out the heat like the quartz bulbed torch lights.When a light needs to be on a ceiling, I use downward aimable bulbs such as the tiny ceramic bodied quartz floods or compact flourescents with built in shade.There are several dimmable flourescent torch lamp brands.I usually stick with the ones that come with the GE Polylux tube.

1. 
   Steve_V | Nov 30, 2001 01:11am | #5

   *I just installed lights in a similar circumstance. My basement ceiling is at 81". I used recessed can lights 8" openingwith flourecent lamps around the perimiter of the room. Then I placed 4 incandesent lamps with 6" opening on 4' centers at the center of the room. Joist spacing required 4' spacing around the perimiter, 28" off the wall.

2. 
   darrel1 | Nov 30, 2001 01:52am | #6

   *A nice little mini-tutorial on office lighting is on the Ikea site:http://www.ikea-usa.com/rooms_ideas/flash_page_light_workspace.aspPersonally, I prefer Halogen whenever possible over flourecents. I think the key is a mix of task lighting and general lighting.

3. 
   piffin_ | Dec 01, 2001 04:10am | #7

   *Here's another linkhttp://www.jlconline.com/jlc/archive/interiors/balanced_lighting/page3.html

2. 
   Rich_Regan | Dec 01, 2001 04:10am | #8

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   I'm doing a basement with 7 1/2 foot ceilings, using cans with a 60w bulb. I just want to evenly light a large open space to be used as a den. I'm going to put them on a dimmer so they can be toned down, but is there a formula I can use to figure how many square feet will need one light?