Roofing materials · Updated November 3, 2026
Roof drip-edge measured-length estimator
Estimate footage-based drip-edge stock lengths from measured eave and rake runs, your selected stock length and chosen allowance.
Estimate a footage-based lower bound for drip-edge stock from measured eave and rake runs. Enter the stock length for the product you selected and an allowance you choose. This calculation runs in your browser.
Enter values and calculate.
List only measured edges included in your project. The allowance is your assumption, not a recommendation. The stock count is a total-footage minimum, not a cut plan; laps, joints, corners, cuts and offcut reuse can change the pieces required. Confirm locations, installation sequence, fastening and material details against the selected roofing system and local requirements.
How to estimate drip-edge stock lengths
- Measure each eave and rake run where the project will use drip edge, and enter each labeled length in feet.
- Add the runs and apply an allowance you select for the project.
- Divide adjusted footage by the selected stock length and round up to a whole stock-length equivalent.
This is a measured-length worksheet. It does not decide which roof edges require drip edge, choose a product profile, determine code compliance or lay out joints and cuts.
Sources and method
- GAF Steep-Slope Pro Field Guide (reviewed November 3, 2026): discusses drip-edge installation at eaves and rakes and gives system-specific installation sequence and fastening guidance. Those installation details are not encoded as universal rules in this estimator.
Formula: adjusted footage = sum of entered measured runs × (1 + your allowance ÷ 100); footage-based stock-length minimum = ceil(adjusted footage ÷ selected stock length). This total-footage calculation does not allocate each run to pieces or optimize cuts.
Related tools: ridge-cap bundle estimator, metal roofing panel estimator, and roof pitch area calculator.
How it works
Enter labeled eave and rake measurements, the selected stock length and any allowance you choose. The estimator totals the entered runs and rounds adjusted footage up to whole stock-length equivalents.
Good to know
Quick answer: how much drip edge do I need?
Add the measured eave and rake runs that will receive drip edge. Apply an allowance you choose, divide by the selected product length and round up. This is a total-footage lower bound, not a cut plan. Reviewed November 3, 2026.
Which edges should I measure?
Measure only the eave and rake runs that your project plans to receive drip edge. GAF guidance discusses drip edge at eaves and rakes, but installation details and requirements depend on the roofing system, product instructions and local requirements.
Does the stock count account for overlaps and cuts?
No. It divides total adjusted footage by the selected stock length and rounds up. It does not position joints, add product-specific laps, optimize cuts or account for reuse of offcuts.
What allowance should I enter?
Use an allowance based on your own project plan and selected product. The calculator does not prescribe a universal allowance or stock length.
Amazon Associates — TODO: apply/approval and configure referral URL — referral link not configured.
Impact — TODO: apply/approval and configure referral URL — referral link not configured.
CJ Affiliate — TODO: apply/approval and configure referral URL — referral link not configured.