I had new cellulose insulation blown into my attic about 4 yrs, ago; the area above the cathedral ceiling was "dense packed". However, not being able to see the area I am not sure if it is really "dense" packed. Anyways, I am now in need of a new roof and I would like to create a ventilated attic. I am willing to remove the necessary decking to provide access to the cathedral portion of the attic.
I have contacted a foam insulation contractor who recommends removing the cellulose in the cathedral portion of the attic and replacing with "open cell" foam after applying a vapor barrier on top of the sheetrock. Is "open cell" the way to go or should "closed cell" be used? I know the closed cell has a higher R value and the rafters are only 2 X 6.
To compensate for the limited R value I propose to add 2 or 3 inches of polyiso under the cathedral ceiling. Will there be a problem with vapor barriers as I don't know if polyiso is considered to be a vapor barrier? The polyiso would be covered with tongue and groove boards.
Also, in the front of the house (where the cathedral ceiling is located) I only have sufficient soffitt area for venting across 1/2 of the area. Should I have soffitt venting on the 1/2 and drip edge venting on the other 1/2 or should I run drip edge venting for the entire area?
I am located in the Albany, NY area.
Thanks for any suggestions!!
I have contacted a foam insulation contractor who recommends removing the cellulose in the cathedral portion of the attic and replacing with "open cell" foam after applying a vapor barrier on top of the sheetrock. Is "open cell" the way to go or should "closed cell" be used? I know the closed cell has a higher R value and the rafters are only 2 X 6.
To compensate for the limited R value I propose to add 2 or 3 inches of polyiso under the cathedral ceiling. Will there be a problem with vapor barriers as I don't know if polyiso is considered to be a vapor barrier? The polyiso would be covered with tongue and groove boards.
Also, in the front of the house (where the cathedral ceiling is located) I only have sufficient soffitt area for venting across 1/2 of the area. Should I have soffitt venting on the 1/2 and drip edge venting on the other 1/2 or should I run drip edge venting for the entire area?
I am located in the Albany, NY area.
Thanks for any suggestions!!