Take the tour ×  Is it necessary to put any kind of vapor
barrier beneath blown in cellulose insulation in an attached
garage? The ceiling is sheetrocked, but that's it. It's a cold,
dry climate (north half of Minnesota), but lots of heat and
moisture will come from vehicles parked beneath; thus, I imagine
a fair amount of ice would develop over the course of the
winter. But...I'm not sure how much ice, or if it's anything to
worry about.  share|improve this question add comment  2 Answers
up vote 1 down vote accepted  It depends on how much ventilation
you've got in your attic.  This article provides the most useful
and thorough information source that I've managed to find.  For
what it's worth, my attic above the garage has the blown in
insulation resting on the sheetrock, but then again, I live in
Alabama.  share|improve this answer So, as you said, it depends
on ventilation. Given that the sheetrock is already installed,
it sounds like vapor retarder paint will be my friend, assuming
I don't have suffici