I am currently correcting insulation issues in my cap code bonus room. I ripped out insulation and installed baffles and installed new r19 insulation in between the roof rafters. The path goes from floor, to behind the 3' knee wall, on top of the baffles to ceiling rafters and back down the other side. Leaving the top as an open air triangle shape ( picture this path of the insulation _ )
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When i look outside after snow, the top of the peak has no snow (above the installed insulation line) but where the insulation is against the roof with baffles behind it and behind the knee wall, there is snow. The top is open to the air from vents on either side of my house. Its also the same air that is flowing thru the baffles and behind the knee space. The room is currently not heated directly, just from heat coming up from the first floor. Does the ceiling insulation need to have a higher R value that that on a vertical and tilted plane? Or is something else I'm not thinking of cause this. I do have 3 light boxes installed in the ceiling. Should i cover these up from above? If so what would be the proper way?