Converting 300 sq ft garage into family room. Installing full floor above garage concrete slab. I want to put a polyethylene vapor barrier on the concrete.
Most places I read recommend 6 mil polyethylene. Home Depot selling for $50.
When cleaning out the garage I found a brand new box of 4 mil polyethylene that my Dad had given me.
Would it be a problem if I used the 4 mil that I have, instead of buying 6 mil?
I have a giant box. Can I double-up the 4 mil, creating a 8 mil barrier?