What downspout means
A downspout is the vertical pipe that carries water from the gutter down to the ground or into a drain.
Also called leader, rainwater leader, conductor.
Where it matters on a gutter job
Undersized or too few downspouts make gutters overflow even when they are clean. Where water lands matters as much as the gutter: dumping it at the foundation is how basements get wet. Add extensions or a tie in to an underground drain as separate lines.
What the model code says
- The code requires the ground to fall at least 6 inches within the first 10 feet away from foundation walls. (IRC 2021, Chapter 4)
Check which code edition your building department enforces for downspout before you quote.
What it costs
The gutter installation cost guide has the typical job at $3,200 and the usual range at $1,300 to $4,200. The guide shows its sources and what moves the price. The gutter installation cost calculator prices a job line by line.
Work it out
- Free calculator: Gutter installation cost calculator
- Cost guide: Gutter installation cost
- Tools, templates and guides: Free gutter resources
Sources: 2021 International Residential Code, Chapter 4, Foundations (ICC). Checked October 9, 2026.