How Exactly is Halo Exterra “Breathable”?

To take advantage of Exterra’s breathability, you’ll need that poly vapor barrier on the warm side to block vapor and moisture from traveling inside the building. Learn more about this code requirement here.
Will Two Layers of Exterra Still Be Permeable?

WILL 2 LAYERS OF EXTERRA STILL BE PERMEABLE? No. Two layers of Exterra will not meet the minimum requirement of being “permeable”, which is 60 ng/Pa-s-m2, or 1 perm. A single layer of Exterra maintains it’s breathability up to a maximum thickness of 2” (71 ng/Pa-s-m2 or 1.2 perms at 2”). Exterra panels are laminated […]