Possible to add Vapor Diffusion to Unvented Attic?

Hello,Is it possible to add a vapor diffusion port to a unvented attic that is closed cell spray foamed at the rafters?  The roof is tongue and groove and in need… Hello,Is it possible to add a vapor diffusion port to a unvented attic that is closed cell spray foamed at the rafters?  The roof is tongue and groove and in need…Read MoreGreenBuildingAdvisor