From what I understand the Pactiv house wrap I got from Lowes "breaths" it is supposed to keep outside moisture out while the inside moisture is allowed to exit through the material. Are you saying that an RV is too small for the Pactiv to act as designed. I am only using the Pactiv as another guard against outside moisture getting to the wood work. I would hate to add it and find it is doing the opposite of what I was hoping it would do. When we are using the camper I'm sure we will crack one of the roof vents the help excess moisture from ourselves escape like we do on out TT