Drip edge
A drip edge is a type of flashing that is installed along the edges of a roof to help protect the roof decking, fascia, and soffit from water damage. It is typically made of metal, such as aluminum or galvanized steel, and is installed along the eaves and rakes of the roof.
The primary purpose of a drip edge is to direct water away from the roof decking and into the gutters, preventing water from seeping under the shingles or other roofing materials and causing damage to the underlying structure. The drip edge also helps to prevent wind-blown debris from entering the roof system.
A typical drip edge consists of a flat vertical flange that is fastened to the roof deck and extends over the edge of the roof, as well as a horizontal flange that is bent downward and away from the roof, directing water away from the roof edge. The horizontal flange is usually perforated to allow water to drain away easily.
In addition to its functional benefits, a drip edge can also enhance the appearance of a roof by providing a finished edge and helping to create a straight and uniform roofline. It is an important component of a properly installed roof and is required by building codes in many areas.