Bubbling drywall seams beneath foam cathedral ceiling
I see some bubbling along two seams in my cathedral ceiling drywall and would like to determine the likely culprit. The ceiling showed no indications of issues for more than one year.
The drywall isn’t sealed perfectly, this is my best guess. Yes, I have a few can lights and an exposed ridge beam that could be better sealed. Or maybe it’s the roof, finding it’s way through.
The ceiling is unvented, witch 6″ of cut-n-cobble rigid foam, followed by 3 to 4 inches of closed-cell spray foam.
This problem is recent, and follows many days of ice on my 12/2 roof. Any thoughts would be appreciated.