Is air gap between insulation and roof deck needed when there is no eve vent?
Hi, in zone 4a. My son’s house. Built in 1942. Addition we are working on probably 1960s.
There is only 2-1/2″ of space between top plate and roof deck.
In section of roof near eve where I only have a few inches to work with, I am going to spray foam in some recycled XPS I have on hand.
Since the eves are not vented, do I still need an air gap between the roof deck and the XPS?
The house really needs a full remodel in the next few years, but since a roof leak damaged the ceiling tiles, my son pulled them out and repaired the leak. I was thinking about a drop ceiling, but also just some strapping and a few inches of XPS for now where rafters are thin.
Thank you for your advice.
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