nospamgoingjag wrote:
I installed John Mansville fiberglass insulation in the cieling in a
new 12 x 24 addition that connects between house and garage. It is
the kind that has plastic all the way around it except for the ends.
It makes it much nicer to handle when installing.

As I went out this afternoon - probably the hottest day in we've had
in Connecticut since I installed the stuff - I noticed a drip coming
from the wood on the cieling. I have 3/8" plywood on the cieling
because I will be nailing up a tin cieling.

There are no pipes up there so I was baffled. I unscrewed a section
of the plywood and the water was coming from the inside of the plastic
in the instullation. I looked at the batt in the next area and it
wasn't dripping but it was clearly full onf condensation. It looks
like maybe each later of plastic is maybe a double and that the
condensation is between the two layers of plastic. The drip appears
to be coming froma batt where the two pieces of plastic have
separated.

Has anyone every heard of this before? I don't remember reading
anything about not using it in a cieling. It is a very shallow (2-3)
pitch roof. So there is very little space between plywood cieling,
plywood sheething and black rolled roofing.

Any thoughts? Looks like I'm going ot have to rip down all the
plywood and insualltion, even though the moisture does not seem to be
in the fiberglass itself?

Thanks for any help.


Hi,
Think, Breathing, vapour barrier, ventillation.
How do you vent the ceiling?