25 Roof Leak Warning Signs (With Photos) — When to Call a Roofer for Repair

Moment #12: Valley debris buildup forcing water sideways

Roof valleys carry a high volume of water, so debris here can trigger fast leaks. Leaves and dirt can create a dam that pushes water under shingle edges and into the underlayment. Even if the roof is otherwise healthy, a clogged valley can cause repeated moisture problems. Clearing debris and checking valley flashing helps reduce leak risk, especially after storms and during fall season.