How to use this calculator
- Choose US customary or metric measurements.
- Enter each eave or gutter run length and the number of identical runs.
- Add differently sized runs as separate entries.
- Enter a stock section length and calculate total linear length and whole sections.
How the calculation works
Each run length is multiplied by its count. Stock sections are rounded up separately for each run, so short remainders are not automatically transferred between unrelated runs.
Formula
Total length = Σ(run length × count) Pieces per run = run length ÷ stock length, rounded up Joints per run = max(pieces per run − 1, 0)
Worked example
Two 24 ft runs and one 15 ft run total 63 linear feet. Using 10 ft stock sections requires three pieces for each 24 ft run and two for the 15 ft run, or eight pieces total.
Project considerations
- Section counts are a linear cutting estimate only.
- Corners, outlets, hangers, downspout locations, slope, and field cuts require separate planning.
- Drainage capacity, rainfall intensity, pricing, and code compliance are not calculated.
Frequently asked questions
Why are pieces rounded for each run?
A continuous run longer than one stock section needs another piece even if a remainder from another run may exist. Actual cut optimization can differ.
Does this size downspouts?
No. It reports gutter length, sections, joints, and endpoints without making drainage-capacity recommendations.