Which of the following materials has the lowest perm rating?
A)1/16- in- thick aluminum sheet
B)4- in.- thick concrete wall
C)4- in.- thick brick wall
D)1/16- in.- thick plastic sheet
E)All of the above materials have the same perm rating.

Question

Quizplus · Accepted Answer

1/16-inch-thick aluminum sheet has the lowest perm rating because aluminum is a metal that acts as an excellent vapor barrier, significantly reducing or nearly eliminating moisture permeability.

Which of the Following Materials Has the Lowest Perm Rating