Will installing Optima fiberglass (closed system) stop the ice damming?
I live in Madison, Wisconsin. I have a cathedral ceiling with 2″x 8″ rafters. The interior is a wood ceiling attached to plywood. I have contacted an insulation contractor and stated I would like to remove the shingles & roof sheathing. He said once I did that, he would seal all air penetrations areas and then install blown Optima fiberglass insulation into the 2″x 8″ ceiling rafters using the BiBs method.
After the Insulation was done, I was going to replace the sheathing and put Ice and Water Shield over the whole area.
The question: Will the sealing of air leaks and installation of Optima fiberglass (closed system) stop the ice damming? Is the Ice and Water Shield over the whole roof overkill?
On one side of the cathedral roof there is a valley on the other side two skylights.
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