i have a circa '64 house with about 4 inches (original) of blown insulation in the attic. being 40 years old, it is pretty compressed and, given my location, woefully inadequate. i purchaced some non-faced FG batts to go over the top and was all set to install them when i noticed that most of the attic has no vapor shield under the cellulose!
so, do i....
a) move the cellulose, install the plastic, put it back, and then install the batts?
b) move the cellulose, chuck it, and install faced batts with a higher r value?
c) let sleeping dogs lie and just fiberglass and forget?
d) run screaming for the hills?
you make the call!
COMMUNITY FORUM
If the attic is ventilated, then no vapor retarder is required.
If it is not ventilated, then the simplest thing to do is to place fiberglass batts on top of the existing cellulose and then to use a paint on the ceiling below that will provide at least a 1 perm rating and act as a vapor retarder.
If it is not ventilated, then the simplest thing to do is to place fiberglass batts on top of the existing cellulose and then to use a paint on the ceiling below that will provide at least a 1 perm rating and act as a vapor retarder.
thanks to the previous owner, i have two gabel vents, an attic fan, a total ridge vent and some very leaky, though not intentionally vented, soffets. for a ~1200 ft^2 attic, this is probably ventillation overkill.
the ceiling already has more coats on it than a sherpa, so one more can't hurt. hopefully that will be barrier enough. it mustn't be too bad as is, b/c there is no sign of moisture in the existing cellulose.
thanks for your 2 cents!
any other opinions out there?
the ceiling already has more coats on it than a sherpa, so one more can't hurt. hopefully that will be barrier enough. it mustn't be too bad as is, b/c there is no sign of moisture in the existing cellulose.
thanks for your 2 cents!
any other opinions out there?
