Ice Water Shield Calculator

Calculate ice and water shield membrane for eaves and valleys.

SHIELD NEEDED
sq ft
eaves and valleys

Usage Tip

Install 2 layers at eaves in cold climates, extending at least 24 in inside the warm wall line.

THE MATH
Area = (Eave + Valley) × (Width ÷ 12) × 2
Where: 2 = double-layer coverage
• A roll covers 200 sq ft
• Extend 24 in inside the warm wall
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