Free Tool
Roof Waste Calculator
Calculate the correct waste factor for any roof type. Get the total squares to order for accurate material estimates and insurance supplements.
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Why waste factor matters for insurance supplements
Insurance companies often use a lower waste factor than what the roof geometry actually requires. If the adjuster estimated 10% waste on a complex hip roof with multiple valleys, the supplement for the correct waste factor can add 1–3 squares of material to the approved scope.
Always document the roof geometry with photos and a detailed sketch to support your waste factor calculation in the estimate.
Appraisly
Appraisly compares your roofing estimate — including waste factors — to the insurance company's scope to identify every discrepancy.