Why is flashing used in roofing?

Flashing is an essential component in roofing systems, primarily used to direct water away from critical areas, such as joints, seams, and transitions where different building materials meet. This is particularly important because these areas are prone to water infiltration, which can lead to leaks and subsequent damage to the roofing structure and the interior of the building.

The effectiveness of flashing lies in its ability to create a barrier, guiding water down and away from vulnerable spots, thereby preserving the integrity of the roof. Proper installation of flashing helps prevent moisture accumulation, which is crucial for minimizing the risk of rot, mold, and structural issues over time. The use of durable materials for flashing adds to the longevity and performance of the roofing system by ensuring that these protective components can withstand environmental stresses.

Other options do not accurately describe the main purpose of flashing. While insulation and aesthetics are important in roofing, they are not the primary functions of flashing. Additionally, adding weight is generally not a desirable feature in roofing design and does not align with the intended purpose of flashing.