Roof Waste Factor Calculator

Right Waste Percentage by Roof Complexity

The Waste Factor Calculator recommends the correct overage percentage to add to your shingle order based on roof complexity. Simple gable roofs use 10%, hip roofs 12-15%, and cut-up roofs with multiple valleys, dormers, and skylights need 15-20% or more. Enter your roof type and pitch and the tool returns the recommended waste factor and the additional bundles to order. Underestimating waste means a return trip to the supply yard mid-job — overestimating ties up cash.