You can insulate the chimney by wrapping unfaced (no paper) insulation
and secure with wire. I insulated all the attic pipes that way,
including the bathroom exhaust piping. I prefer the batts to blown-in
insulation. Do not block vents--your roof needs to "breathe."

On Sat, 8 Nov 2003 14:04:25 -0500, "Alexander Galkin"
wrote:

I am adding insulation to the attic that already has insulation. I have a
heater chimney that goes through the attic. Can I use John Manville Kraft
R-19 unfaced batts to add insulation to the attic? The package says its for
wall/floor/crawl spaces. I assume it can be used for attic too. Can batts
touch heater chimney? The chimney actually has two pipes, one inside
another. The inner pipe is very thin aluminum pipe while outer pipe is
regular duct metal pipe. If batts cannot touch chimney can I use thermofiber
insulation around the chimney and keep batts 3" away from it? I think
thermofiber insulation does not burn and can touch hot objects.