Loose wool in the attic, how to seal against the chimney?

[Skittele]

As the title suggests, if I need to install a chimney and have loose-fill insulation in the attic, how do I seal the space between the round chimney and the sawed hole in the ceiling? That is, the passage between the room's interior ceiling and the attic, not between the attic/exterior roof.

Probably the wrong forum, mod can move it if it fits better somewhere else.

 

[Ursidae]

As I understand how it's done here at home, you have a special heat-resistant vapor barrier fabric that you wrap around the chimney and tape to the existing vapor barrier. Then you should have rock wool closest to the chimney.