Guessing this is the best forum to ask this: I have a wood burning fireplace on the first floor. It is served by 12" double-wall metal chimney pipe that extends through a chase area, through the attic, and into a wooden chimney box on the roof. Where it passes into the attic, there is a metal firestop installed. However, other than that, there is no other "barrier" to keep the blown cellulose I have in the attic from settling against the pipe, which I don't think is correct. Should I wrap the pipe with Roxul on top of the firestop to at least the depth of the blown cellulose? Or how else can I stop the cellulose from butting up against the pipe?