How much gutter do I need?
Gutter is bought by the section, so the run of your eaves drives everything:
Sections = eave length ÷ section length, rounded up
Add up every roof edge that will get a gutter, then divide by your section length — usually 10 ft — and round up. On top of the gutter you add a downspout every 30–40 ft of run (at least one per run) and a hanger about every 2 ft to keep it from sagging.
Gutter parts you'll need
| Part | How many |
|---|---|
| Gutter sections | Eave length ÷ 10 ft |
| Downspouts | 1 per 30–40 ft of run |
| Hangers | 1 every ~2 ft |
| End caps & corners | Per run ends and each corner |
Gutter materials compared
The material sets the price and how long the gutters last:
| Material | Relative cost | Lifespan |
|---|---|---|
| Vinyl | $ (lowest) | 10–20 yrs |
| Aluminum (most common) | $$ | 20–30 yrs |
| Galvanized steel | $$ | 15–20 yrs |
| Copper | $$$$ | 50+ yrs |
K-style vs. half-round, and what size
K-style gutters have a flat back and a decorative front and hold more water than the same-width half-round, which is why they're on most homes. For size, 5-inch K-style suits the average roof; step up to 6-inch with 3×4-inch downspouts for large or steep roofs and heavy-rain regions, since they carry roughly 40% more water and clog less. Seamless aluminum (rolled on-site) avoids the leak-prone seams of sectional gutter.
How much do gutters cost?
Gutter material runs about $4–$15 per foot — vinyl and aluminum at the low end, steel and copper higher — before downspouts, elbows, and hangers. Seamless and professional installation cost more than DIY sectional gutter, but leak less over time.
Good to know
- Slope toward downspouts. Pitch the gutter about 1/4 in per 10 ft so water drains instead of pooling.
- Size for the roof. 5-in K-style suits most homes; go 6-in with 3×4 downspouts for big or steep roofs.
- Send water away. Extend downspouts well past the foundation — or tie them into a French drain.
- Seal the joints. Sectional gutters need gutter sealant at every seam, end cap, and outlet.
Installing gutters: the basics
Sectional gutter is a manageable DIY job on a single-story home. Snap a chalk line along the fascia that drops about ¼ inch per 10 feet toward each downspout, so water always runs downhill. Mount hangers into the fascia or rafter tails every ~2 feet along that line, hang the gutter, and cut outlets where the downspouts go. Attach the downspouts with elbows to reach the wall, strap them down, and run the bottom elbow well past the foundation. Finally, seal every seam, end cap, and outlet with gutter sealant. Work from stable scaffolding or with a helper footing the ladder — never overreach from a single ladder along a long run.