Free Gutter Length Calculator
Calculate the total linear feet of gutters and number of downspouts needed based on roof edge measurements and building dimensions.
Total Gutter Length
100 ft
Total Gutter Length vs Front Edge Length
How to Calculate Gutter Length
Formula
Total Length = Front + Back + Left Side + Right Side
Sections = ceil(Total Length / Section Length)
Downspouts = ceil(Total Length / Max Spacing)
Measure every roof edge that needs a gutter. Standard residential gutters are 5 inches wide (K-style) and sold in 10-foot sections. Each run of gutter should have a downspout no more than 40 feet from the end or high point of the run.
Slope
Gutters must slope toward the downspout at about 1/4 inch per 10 feet of run. For runs longer than 40 feet, slope from the center toward downspouts at each end.
Example Calculation
A ranch home with 50 ft of gutter on front and back, no side gutters, 10-ft sections, and 40-ft downspout spacing.
- 01Total gutter = 50 + 50 + 0 + 0 = 100 ft
- 02Sections = ceil(100 / 10) = 10 sections
- 03Downspouts = ceil(100 / 40) = 3 downspouts
- 04No corners needed for straight runs
Frequently Asked Questions
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