Abstract: Embodiments of the present invention relate to the field of construction, and more particularly to waterproofing the exterior of buildings. Specific embodiments of the invention provide devices for preventing moisture leakage between a roof and chimney, where the roof and chimney intersect and at the corners of the chimney. The present invention in particular provides flashing comprising: an L-shaped planar member having an interior L-shaped edge; and two flanges connected with a web and integral with the L-shaped member, disposed along the interior L-shaped edge, and having a continuous upper edge; wherein the interior edge of the L-shaped member is shorter in length than the continuous upper edge of the flanges.