Attic Plywood Air and Vapor Barrier
I have been planning to use a 5/8″ plywood + tape to create my air/vapour barrier between my conditioned space and the attic. My walls are ICF and the plywood would be taped to the ICF foam.
I am in zone 6A in southeast British Columbia. It sounds like the local inspector may still want us to use a poly barrier. I wanted to avoid this because of added cost, durability, and the PITA nature of any penetrations.
Is there any code/literature that I can point to to help ease his mind? I’ve found these articles, but I would classify them as good, but not great resources:
GBA Detail Library
A collection of one thousand construction details organized by climate and house part