For the second part, a surfacing sheet is mopped to the felts. Counterflashing The last part of a vertical flashing is called counterflashing. Counterflashing is usally made of metal. It shields the top edges and joints of the base flashing. The second kind of flashing is horizontal.
Horizontal flashings have to be installed at drains, roof edges and vents.
These flashings are installed around objects on the flat surface of flashing a roof. These flashings are made of felts, asphalt, flashing cement, lead and other metals. Surfacing The third part of a BUR membrane is surfacing. There are three types of surfacing. One type is aggregate.