Roof leak argument for open-cell vs. closed-cell under roof deck
I have heard the same general argument used by several insulation installers (even BPI certified ones). They say that the use of open cell foam affords better leak detection protection and drying to the inside when it sprayed under the roof deck rather than closed cell foam.
GBA seems to favor closed cell based on my reading of the site posts. The house is in Zone 4 and has a standing seam metal roof that is about 6 years old. Any additional thoughts?
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