I received this question from a reader: "I'd like to add some recessed lighting to my son's bedroom. He currently has nothing in the ceiling. Are there any "rules of thumb" for recessed, and anything I need to know before I buy?"
It's a bit hard to answer the question in a general sense, but these are the questions we'd need to ask:
~ Is there insulation in the ceiling? (If so, you need an IC-rated housing.)
~ Do you have access to the ceiling from above, or will you be cutting in holes from below? (If you have access, you use a "new-construction" type housing. If not, you use a "remodeler" style.)
~ How high are the ceilings? (If they are 8-9' high, we like 5" recessed apertures. If higher, you may want 6" lights.)
~ Do you want general illumination, or do you want to highlight or spotlight certain architectural features or artwork? (If general, I'd just use a basic white or black baffle with an incandescent flood bulb. If highlighting, I would recommend a low-voltage MR16 fixture.)
To answer her question as for "rules of thumb", I would say most average-sized bedrooms where you want general illumination would need four 5" regular downlights. We place them 2-3' from the walls, and then they're usually about 4-6' apart.
Hope that helps!