When roofing your home it’s important to consider all factors of a proper Roofing system.  The underlay, venting and flashing all play a role in how well your roof will shed water and prolong the life of the asphalt shingles.  Drip flashing can help prevent rotten plywood under shingles.  It is installed along the Eaves of the roof, the lower horizontal edges of any roof, and is designed to prevent water from creeping back up under the shingles as it travels towards the eaves trough.  This is particularly important in lower sloped roofs where water is shed at a lower rate.  Just as any penetration in a wall such as a window or door must have proper flashing, the Drip flashing plays an important role in prolonging the health of your roof deck and subsequently the shingles.