I have 0 insulation in my attic. It’s going to be a couple months before MassSave can come out and insulate (due to a few barriers that need to be addressed before installation). In the meantime, I want to add some insulation to keep my extremely high costs down.

I can access some low cost reuse XPS or discounted mineral wool.  Thinking about putting down between R10-20 (as much as I can get my hands on inexpensively). Am I creating a “drying” problem in my ceiling if I use XPS on the attic floor? I understand that there’s a humidity stack effect, and want to be sure that I’m not cooking up a recipe for disaster in the future if I add XPS panels before MassSave lays down another several inches of cellulose.