How far must valley flashing extend from the center line?

Valley flashing is a critical component in roofing systems, particularly where two slopes meet to form a valley. Proper installation of valley flashing is essential for directing water away from the roofing materials and preventing leaks.

In North Carolina Residential Code, valley flashing must extend a specific distance from the centerline of the valley to ensure adequate coverage and proper drainage. The requirement for valley flashing to extend at least 11 inches from the centerline helps to manage potential water flow effectively. This distance is designed to ensure that any runoff from the roofing surfaces does not infiltrate beneath the shingles or roofing materials, which could lead to water damage or rot.

This extension also provides a sufficient overlap with other roofing materials, aiding in the creation of a watertight seal. Adhering to the 11-inch guideline is crucial for the longevity of the roofing system and maintaining the integrity of the structure's insulation and framing. Making sure flashing extends to the specified distance mitigates the risk of leaks and contributes to overall building safety and durability.