Pieces of sheet metal used on roofs to cover joints, such as where the roof meets the wall, or around a chimney or skylight, to protect them and prevent water leaking through.

Things you need to know

Using flashing to cover joints on a roof will protect against weather-related water damage by preventing water from passing through those joints into the house. It is important to be aware of galvanic corrosion and not put two metals in contact that will corrode. This means taking into account the building materials that the flashing will touch.