Drip edge metal, valley flashing, dormer, chimney, and kickout flashing are types of roof flashing that shed water away from the connections between roofs, walls, chimneys, and other building assemblies
The IRC is a thick book, but there is relatively little aimed at decks. A few sections have a few sentences dedicated to construction of safe and durable decks.
Vapor barriers cause a lot more harm than good in many parts of North America. Understanding vapor barriers begins with knowing what it means to be one