Will I have a dew point problem in the wall cavity?
I’m a contractor living in Southwestern NH and designed an insulation envelope for a house. From inside to the outside it consists off 1/2″ plaster, 2×4 with 3-1/2″ R-13 blown-in cellulose, 1/2″ CDX plywood and a 5-1/2″ polyurethane SIPS R-32. The SIPS has 1/2″ blue board, 4-1/2″ of urethane foam and 1/2″ OSB. All seams in the panel will be drilled and foamed.
Does the cellulose move the dew point into the 2×4 cavity?
The total R value of the wall is R-45.
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