Hi, I am replacing several non-IC recessed lights with IC ASTM E283 lights in my bathroom. The bathroom has 3 exterior walls so it gets quite cold in winter. It is also large, 10x10.
The old lights had "dams" build around them to keep the insulation several inches away. So, there are essentially several small squares in my ceiling without insulation.
My main question is whether I should used faced or unfaced insulation for these squares? Is it OK for the kraft paper to be in direct contact with the lights? Or should I use unfaced insulation and not worry about having a small portion of my ceiling without a vapor barrier?
As for technique, I was thinking of cutting a square piece to fit the space, and then cutting a circle out of the square for the light to fit through. Maybe I should put an unfaced piece above the light too? (Eventually I hope to add a second layer of insulation to the attic above the bathroom.)
Indiana may not require a true vapor barrier, but you need an air barrier. Having no insulation in several spots is not good. Recessed lights/fans are a real PITA, as they SHOULD be air sealed and insulated. You may have to build an air-tight, well insulated box, installed from above, and run your exhaust through that. Make sure your exhaust pipe is air tight, too, so you are not wetting your insulation and attic. Leave the fiberglass "insulation" at the store, and use mineral wool if it is going to get hot; cellulose or cotton if it won't get hot. The mfgr should be able to tell you how far from the lights your insulation needs to be.