Basement Insulation: Ideal perm rating?
![](https://secure.gravatar.com/avatar/41aca3cb6c84d79c2bc03efec98ebf94?s=52&d=https%3A%2F%2Fimages.greenbuildingadvisor.com%2Fapp%2Favatars%2F200x200%2Fa.png&r=g)
Hello GBA,
What is the ideal perm rating for insulation being installed on basement walls in Zone 5? Is there a strong preference toward either XPS, EPS, or a closed cell spray foam? Lets assume that all basement moisture issues are taken care of.
I believe that controlling the air movement is the most important component of a dry basement assembly, but I also do have concerns about vapor diffusion and condensation at the block.
So many opinions going around out there….
Thanks!
-Art
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb1.png)
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb2.png)
Replies
"Lets assume that all basement moisture issues are taken care of." Not being a pro, I would wonder if that is a valid assumption. What does buildingscience.com say?