What does "flashing installation" prevent in roofing?

Flashing installation is crucial in roofing systems as it serves to protect vulnerable areas from water infiltration. Specifically, flashing is installed at joints, seams, and transitions where different materials or roof planes meet, such as the intersection of a roof and a wall, around chimneys, and in valleys where water might accumulate. The primary function of flashing is to direct water away from these critical areas, which are typically prone to leaks due to the potential for water pooling or running off in unintended directions.

By preventing water leaks at joints and seams, flashing ensures that the roofing system maintains its integrity, avoiding water damage that could lead to mold growth, structural compromise, or deterioration of roofing materials. This makes it an essential component of effective roof installation and maintenance.