What is best option to insulate Zone 5A attic?
I live in W Hartford, CT (Zone 5A) and have an attic that needs insulating.
I assume the insulation will need to be in the 2×8 rafters since we have AC
ductwork running thru the attic space and some batt insulation in the attic
floor covered by wood. We have a new roof with a ridge vent and no vents in
the eaves as the roof has no overhang. We have had issues with ice dams
given limited insulation in the eaves.
I would appreciate information the best way to solve. We have been
a- spray foam in rafters (closed cell vs open cell?);
b- rigid foam in rafters with careful taping/sealing;
c- rigid across rafters and sealed, with cellulose packed in behind; or
e- no foam — cellulose in rafters, maybe gussetted down for more depth
(though ideally would not lose attic space).
Insight appreciated. Thanks.
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