I hear a lot of talk about vapor barriers, especially in the colder climates. I tried using a space blanket once on a mid-20'F night, placed inbetween my double layers on the WBBB, and whilst it kept my UQ free from moisture, it created moisture above it between the blanket and my back - I got cold through the night because of it.
What did I do wrong?
Can someone give me a 101 insight into vapor barriers, their use, and why one should consider using one?
Thank you in advance.