The building component used to connect portions of a roof, deck, or siding material to another surface such as a chimney, wall, or vent pipe. Often made out of various metals, rubber or tar and is mostly intended to prevent water entry.

flashing detail

Example of a flashing detail for siding applications. This detail comes from an out of print USDA manual: Wood-frame House Construction that was last edited in 1970. Modern flashing standards are quite similar. A good example for the durability of many building standards.

See also: Q&A: Construction Details For A Deck, Q&A: Roofs