Mechanical & Roof

Gutter Length & Downspout Calculator

Calculate linear feet of 5" or 6" rain gutters, downspouts (1 per 35ft rule), end caps, corners, and fascia hangers.

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Input Parameters

Enter dimensions and specifications to estimate materials.

Instant
ft
ft (standard 35-40)
Real-time verified calculation
Your Result

Total Gutter Footage

120Linear Feet
Calculation Breakdown

Downspouts Needed

4downspouts

Fascia Hangers (every 2ft)

62hangers

End Caps

4caps

10ft Sections

12sections

Material estimates include recommended trade waste buffer. Always confirm dimensions on site prior to ordering.

How The Calculation Works

Formulas, material coverage assumptions, waste buffers, and rounding standards.

Roof drainage rules recommend at least one downspout for every 35 to 40 linear feet of gutter.

Hidden screw hangers are installed every 24 inches along the fascia board.

End caps are required at the two terminates of every continuous run.

Standard Formula: Downspouts = ⌈Gutter Run / 35ft⌉ | Hangers = ⌈Gutter Run / 2ft⌉

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Frequently Asked Questions

Practical installation guidance and purchasing tips for gutter length & downspout calculator.

5-inch gutters are standard for moderate rainfall and low-slope roofs. 6-inch gutters hold 40% more water volume, making them ideal for metal roofs, steep pitches, or heavy rain areas.