Roof Valleys Calculator

Linear Feet & Valley Material Required

The Valleys Calculator returns the linear feet of valley material — ice & water shield, W-metal, or closed-cut valley shingles — needed for every valley on your roof. Enter the total linear feet of all valleys and select an installation type and the tool returns roll count or piece count with proper overlap. Valleys carry the most water of any part of a roof, so accuracy here is critical. Pair with our Flashing and Underlayment calculators for full waterproofing coverage.