Gutters & Roof Drainage
~9 min read · Size up gutter slope, discharge and overflow patterns that put water against the foundation.
Gutters are foundation protection wearing roof clothing: their job is catching thousands of gallons and putting it far from the basement. Slope, secure hangers, tight seams, and downspouts that discharge away — four checks that prevent the wettest findings in the house.
The collection system
Gutters should slope toward downspouts (roughly 1/16–1/8 inch per foot — standing water and sediment lines betray flat or back-pitched runs), hang securely (spike-and-ferrule pulls out; hidden hangers hold — sagging sections dump overboard), and keep seams and end caps tight (drip stains and tiger-striping below mark leaks). Sizing mismatches show as overflow evidence at inside corners and long runs: stained siding, mulch blast-craters, and mud splash on the skirt.
- Water and sediment standing = slope failure
- Sag and pullout at hangers dump water at the fascia
- Overflow evidence: stains, splash erosion, tiger stripes
Downspouts and discharge
Downspouts must be attached, unclogged (rattle test, stains at joints), and — the finding that matters most — discharge away from the foundation: extensions/leaders carrying water past the backfill zone, splash blocks aimed downhill, or buried drains verified to daylight. A downspout ending at the foundation corner is a basement-water generator; two roofs draining to one corner is the classic wet-corner source. Cross-reference with grading and interior moisture findings.
- Discharge PAST the backfill, downhill
- Corner-dumping downspouts pair with wet-basement evidence
- Buried drains: unknown destination = stated limitation
Maintenance and climate details
Debris loading (check the gutters if walkable/visible), gutter guards that shed or shelve debris, ice damage — bent and torn sections, and the ice-dam interplay: clogged gutters hold the frozen reservoir that backs melt water under shingles. Fascia rot behind gutters closes the loop with the trim inspection.
Worked example
The northeast basement corner shows efflorescence and a damp floor line. Outside that corner: two downspouts (front and side roofs) both end at the foundation with cracked splash blocks aimed sideways; the gutter above holds an inch of standing water with sediment; and soil at the corner is eroded into a channel. Connect the system.
Trace backward from the wet corner: the eroded channel is the surface signature of concentrated discharge; two downspouts delivering both roofs' water AT the corner, with derelict splash blocks, inject it into the backfill; the standing water above says the gutter run is back-pitched, encouraging overflow at this same end in hard rain. The interior efflorescence and damp line are the basement's receipt. Report as one system finding: re-pitch the gutter, extend both downspouts well past the backfill (downhill), regrade the eroded corner — and predict the interior symptoms improve; monitor afterward. Cheap corrections, expensive symptom — the gutter section's entire theme.
Common exam pitfalls
Inspecting gutters without following the water to the ground.
The system ends where the water lands — corner discharge findings matter more than clean troughs.
Crediting buried downspout drains sight-unseen.
Unknown destinations get a limitation note plus a search for surcharge evidence at the foundation.
Missing the interior cross-reference.
Wet-basement evidence pairs with roof-drainage findings — report them as one mechanism.
Pitch it, hang it, seal it, and send the water somewhere else's downhill.
Recap
- Slope toward downspouts; standing water = finding
- Secure hangers and tight seams; watch for overflow evidence
- Downspouts discharge past the backfill zone
- Corner-concentrated discharge pairs with basement moisture
- Clogged gutters feed ice dams
- Report gutters, grading, and interior moisture as one system
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