Gutters get treated as a cosmetic trim piece that occasionally needs cleaning. They are actually the drainage half of your roof system, and most of the expensive rot we cut out of houses starts with water that got past a gutter.
A single inch of rain on a 2,000 square foot roof sheds well over a thousand gallons of water. All of it arrives at the roof edge and has to go somewhere. Gutters decide whether that somewhere is the yard or your fascia, soffit and foundation.
What gutters actually protect
- The fascia board behind the gutter, which holds the gutter and closes the roof edge. Once it rots, the gutter loses its anchor and starts pulling away, which accelerates everything.
- The soffit and its intake vents. Soaked soffits stop ventilating, and an attic that cannot breathe cooks shingles from below and builds ice dams in winter.
- Siding and windows. Water sheeting off an overflowing gutter runs down the wall and finds every seam and flashing detail.
- The foundation. This is the big one. Water dumped at the base of a wall saturates soil, which expands and contracts, which moves foundations and pushes water into basements and crawl spaces.
- Landscaping and walkways, which channel water back toward the house when they erode.
How gutters fail
- Clogging. Leaves and shingle granules form a dense sludge that holds water, adds weight and freezes solid in winter.
- Wrong pitch. A gutter needs a consistent slope toward the downspout, roughly a quarter inch of fall over ten feet. Flat runs hold standing water; reversed runs overflow at the far end.
- Undersized gutters or too few downspouts. Five-inch K-style is standard residential; six-inch handles large or steep roof planes and heavy Midwest downpours far better. Downspout count matters as much as gutter size — a long run draining to one outlet will back up regardless of how big it is.
- No gutter apron or drip edge. Without metal directing water off the deck edge and into the trough, water clings to the underside of the shingles and runs behind the gutter onto the fascia. This is one of the most common and most destructive details we find.
- Failed seams and loose hangers. Sectional gutters leak at joints as they age; seamless runs largely remove that failure point.
- Downspouts discharging at the wall. Getting water into the gutter and then dropping it against the foundation solves nothing. Extensions should carry it several feet out, onto grade that falls away from the house.
The granule tell
Black, sandy sediment in the trough is shingle granules, and it is diagnostic. Some granule loss is normal in the first months after installation as loose material washes off. Heavy accumulation on an established roof means the shingle surface is wearing or was damaged — frequently by hail. If you are seeing piles of grit at the downspout outlets, that is a reason to have the roof itself inspected, not just the gutters cleaned. See our article on spotting hail and wind damage.
Winter: where gutters and roofs collide
In a Midwest winter, a clogged gutter becomes an ice trough. Meltwater running down a warm roof hits the cold overhang, refreezes and builds a dam, and standing water backs up under the shingles. The gutter does not cause the ice dam — heat loss and poor ventilation do — but a full, frozen gutter makes it dramatically worse and adds enormous weight to the fascia. Our full explanation is in ice dams and freeze-thaw damage.
Gutter guards, honestly
Good guards on a properly pitched, correctly sized gutter meaningfully reduce cleaning frequency. They do not eliminate maintenance: fine debris, shingle grit and pine needles still accumulate, and guards can shed water past the gutter entirely in a hard rain if they are the wrong style for your roof pitch. Treat them as a reduction in work, not an end to it, and be skeptical of anyone selling them as permanent.
A year-round rhythm for Missouri and Illinois homes
- Spring. Clear seed pods and winter debris. Check for hangers pulled loose by ice and for seams that opened over the winter.
- Summer. Watch during a hard rain. Overflow points, waterfalls at corners and drips behind the gutter tell you more than any inspection on a dry day.
- Fall. The important one. Clean after the leaves are down, not during. Verify every downspout runs clear and every extension is still in place.
- Winter. Watch for icicles and ice buildup at the eaves — a signal about attic heat loss as much as about the gutters.
We install seamless gutters, gutter guards, and the drip edge and apron details that keep water out of the fascia in the first place. See gutters and downspouts, and if you are replacing a roof, replacing tired gutters at the same time costs far less than doing it as a separate trip.
Not sure which way your roof goes? We will tell you straight, in writing, after a free inspection. Call 1-800-564-6232 — answered 24 hours a day — or book an inspection online.
Frequently asked questions
How often should gutters be cleaned?
Twice a year is the baseline for most Midwest homes, in late spring and after leaf fall. Under heavy tree cover, three or four times. Watch the gutters during a hard rain a couple of times a year, since overflow tells you what a dry inspection cannot.
Should I get 5-inch or 6-inch gutters?
Five-inch K-style handles most residential roofs. Six-inch is worth it on large roof planes, steep pitches that accelerate runoff, long runs with few downspout locations, and homes that have historically overflowed. Downspout size and count matter as much as trough width.
Can bad gutters really damage my roof?
Yes. Water backing up behind a gutter rots the fascia the gutter is fastened to, soaks soffits and their intake vents, and works under the roof edge into the decking. In winter, a frozen gutter contributes to ice damming that drives water under the shingles.
Do gutter guards actually work?
Quality guards on correctly pitched, correctly sized gutters substantially reduce how often you need to clean them. They do not make gutters maintenance-free, and the wrong style for your roof pitch can cause water to overshoot in heavy rain.
Why is there black sand in my gutters?
Those are asphalt shingle granules. A little is normal on a new roof. Heavy accumulation on an older roof means the shingle surface is wearing out or has been damaged, often by hail, and the roof should be inspected.