 Even though it's a cup, I don't have it all the way done yet, though, but I can still see water trying to drip through the insulation. I got R14. Well, here's what I would do. What kind of tape did you use? Did you use aluminum tape? Yeah, the stuff for actual duct work. All right. So you use aluminum tape, and you can also use, like, silicone caulking tape.