GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

grace tri-flex XT adequate for unvented roof assembly?

user-7601308 | Posted in GBA Pro Help on

I have a hip roof that butts up to a wall, and it seems like it would be easier to do an unvented assembly with rigid foam above the sheathing than to try to vent the hips. I have 7/16 OSB sheathing that is untaped, with a layer of grace tri-flex XT on top of that. Will that serve as an adequate air barrier or adequate layer before 3 inches of foil faced polyiso? the top layer of polyiso will be foil taped. planning to put either corrugated master rib, or standing seam on top. Does corrugated metal roofing, in essence, self vent?


GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. Expert Member

    User ...308,

    I answered the first part of this where you posted it elsewhere.

    Metal roofs with large corrugations can provide some venting, but on its own it is not code complaint, and it is difficult to vent hipped cathedral roofs.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |