What is the purpose of flashing installed on a roof?

Flashing plays a critical role in roofing systems by serving as a protective barrier against leaks. It is typically made of materials like metal or waterproof membranes and is strategically placed at joints, seams, and transitions where the roof meets vertical structures, such as chimneys, walls, or skylights. These areas are particularly vulnerable to water intrusion, and the installation of flashing helps to channel water away from such points, effectively directing it off the roof and preventing moisture from penetrating the underlying materials. This prevention is vital in maintaining the integrity of both the roof and the building structure beneath it, ultimately extending the lifespan of the roof and safeguarding against water damage or mold growth.

While aesthetic appeal, insulation, and roof drainage are important aspects of roofing design and function, they do not directly relate to the primary purpose of flashing, which is to act as a waterproofing measure to protect against leaks.