Project Overview
Leak traced to a woven shingle valley on a two-story home after heavy rain. Shingles in the valley showed wear consistent with concentrated runoff and the original closed valley had never been lined with metal.
Analysis
Closed woven valleys rely entirely on shingle overlap, which wears at the choke point of the run-off path. No metal liner was present, and water had traveled past the overlap during a severe rain event.
Process
Shingle removal along valley; full-length ice-and-water shield; W-valley metal install; parallel shingle cut; edge-sealing; controlled water test.
Outcome
Leak stopped on the water test. Valley now has a durable metal liner that will outlast the surrounding shingles and handle concentrated runoff cleanly.
