Attic Closed Cell Foam Insulation
There is 300 difference there but the cost they give you is about a third difference and open cell foam at 12 inches will not give you the performance of 2 inches of closed.
Attic closed cell foam insulation. Using spray foam insulation in an unvented attic application both low density open cell and medium density closed cell spray foam can be used in an unvented attic to provide the needed thermal resistance and airtightness. This medium density spray foam is a closed cell spray foam that is typically used where there is the need for r value insulation per inch possible. Closed cell foam can also increase the racking. This type of spray foam offers the specific benefits of continuous insulation interior wall cavity fill and unvented attic applications.
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