Perimeter → stock lengths

Drip edge and flashing length calculator

Combine eave, rake, valley, and other flashing runs, then estimate stock pieces with waste and end laps.

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Drip edge and flashing length calculator

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Example values are shown. Replace them with field measurements and verify the unit beside every entry.

ft
ft
ft
ft
ft
in
%

How this worksheet works

From measured runs to stock lengths

This calculator totals several flashing categories while keeping the measured length visible. Stock-piece count uses effective installed coverage after the entered end lap.

How to use it

  1. Enter eave, rake, valley, and other required flashing lengths.
  2. Enter stock-piece length, required end lap, and waste.
  3. Calculate and round up to whole stock lengths; keep unlike flashing profiles separate when ordering.

Useful for

  • Drip edge perimeter takeoffs
  • Valley or wall-flashing length checks
  • Stock-length ordering with laps

Assumptions

  • All entered runs use the same stock length and end lap
  • Waste is applied to total measured length
  • The first stock piece in a run is conservatively treated using effective coverage

Limitations

  • Does not distinguish profiles, gauges, metals, colors, or corners
  • Transitions and fabricated details require separate takeoffs
  • Very short separate runs can require more pieces than one combined total

Common checks

Questions about this calculator

Why enter an end lap?

Adjacent stock lengths overlap, so each additional piece covers less than its full physical length.

Can I combine drip edge and valley metal?

Use the total for planning only. Order each profile, material, and size as a separate line item.