Void space behind drywall
Is it OK to leave a void or empty space between the back of the drywall and spray foam insulation if the required R value is reached without filling the cavity? The insulation contractor has suggested only spraying 3″ of closed cell foam against the inside of the sheathing of a 2 x 6 framed wall. This would leave approximately 2.5″ of void. Northern NJ, 1000′ elevation.
thanks in advance.
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