Code compliance of using UHMW (Ultra High Molecular Weight Polyethylene) shims for deck leveling
I don’t think there will be any issues using UHMW. It will never rot and it can be drilled and screwed it wont break under impact so I only see advantages it is a vapor / moisture barrier also. I have used it for pool projects but not often because of cost, I live just south Benton , lane and Lynn counties and they would not have a problem with UHMW.