Explain what is meant by permeability and describe how to interpret the permeability ratings of vapor retarders.

Question

Quizplus · Accepted Answer

The Answer is The permeability of vapor retarders is rated in perms, a measure of the rate of transfer of water vapor through a material. Vapor retarders have permeability ratings of 1.0 or lower. Materials with a perm rate of ( 1 perm) are considered impermeable, (>1 to 10 perms) semi-permeable, and (>10 perms) permeable.

Explain What Is Meant by Permeability and Describe How to Interpret