Home / Roof Repair
This is the single most useful thing a homeowner can understand about roof leaks, and it is the reason so much money gets spent repairing the wrong thing.
Water entering a roof assembly does not fall straight down. It lands on the top surface of the underlayment or the underside of the deck and then travels along whatever path gravity and surface tension offer — down the slope of a rafter, along the top edge of a purlin, sideways across a run of sheathing, down the side of a truss chord — until it reaches a point where it can drip free. That release point might be fifteen or twenty feet from the actual entry point, on the other side of the attic, and often on the opposite side of the room from where you would guess.
A repair crew that goes straight to the roof surface directly above the ceiling stain and seals whatever looks suspicious will frequently find nothing wrong, apply sealant anyway, and hand you an invoice. The leak returns with the next sustained rain, because the entry point was never touched. In Seattle, where a leak may be actively wetting framing for months before a stain becomes visible, this pattern is expensive in a way that goes well beyond the repair bill.
Real leak detection works upstream from the symptom, and it starts inside the house rather than on the roof.
Where there is access, we start in the attic with the lights off and a flashlight held low. Daylight visible through the deck is obvious. Less obvious and far more common are the tracks: dark staining trails on rafter sides, rust rings around nail shanks, water-marked insulation, and the pale mineral outlines left by evaporated water on the underside of sheathing. Those tracks are a map. Followed uphill, they lead to the entry point rather than the drip point.
This step is skipped constantly in Seattle and it changes the entire diagnosis. In a mild, wet winter, warm moist indoor air that reaches a cold attic condenses on the underside of the roof deck. The result is damp sheathing, wet insulation, and ceiling staining that looks exactly like a roof leak but is not one. The tells: moisture distributed broadly and evenly across the deck rather than concentrated along a path, frost or beading on nail points across a whole slope, symptoms that worsen on cold clear nights rather than during rain, and a bathroom or dryer vent terminating into the attic instead of through the roof. Sealing the roof does nothing here. Fixing intake ventilation, sealing attic bypasses, and correctly terminating exhaust ducts does. A contractor who cannot tell you which of the two you have is guessing.
Once we know the entry zone from the inside, we work the exterior in order of statistical likelihood: roof-to-wall junctions and missing kickout flashing, chimney counter flashing and crickets, skylight head and side flashing, plumbing vent boots, valley terminations, and only then the shingle field itself.
When the source is still ambiguous, we test with a hose from the bottom of the suspected area upward, isolating one component at a time, with an observer inside the attic. Starting low and moving up in stages is the entire method — flooding an entire slope at once tells you a leak exists but not where it entered.
Where a roof slope dies into a vertical wall, a kickout flashing at the bottom of the run is supposed to redirect concentrated water away from the siding and into the gutter. It is small, cheap, frequently omitted, and its absence sends a stream of water directly behind the wall cladding. The damage accumulates inside the wall assembly for years before anything shows on a ceiling, which is why this failure is often discovered during a siding project rather than a roofing one.
Masonry and roofing move at different rates and the joint between them is a maintenance item, not a permanent seal. Counter flashing should be let into a mortar joint and lapped over the step flashing. Where a chimney is wider than about 30 inches on the upslope side, it needs a cricket — a small peaked diverter that splits water around it. Missing crickets create a debris and water trap that fails on schedule.
The rubber collar around a vent pipe has a shorter service life than the shingles around it, typically failing at 10 to 15 years as UV and thermal cycling crack the elastomer. This is one of the most common single-point leaks we find, and one of the cheapest to fix if caught before the deck below it softens.
Older units leak through failed seals and degraded flashing kits; a surprising number leak because they were installed with sealant instead of a proper step-and-head flashing assembly. Also worth ruling out: interior condensation running down the glass and pooling at the frame, which looks identical to a leak from below and requires a completely different fix.
Valleys carry the concentrated runoff of two slopes. Under Seattle's tree canopy they also collect needles, maple seed, and moss, which dam water and hold it against the assembly. Debris accumulation converts a functioning valley into a slow, persistent soak.
Storm damage rarely looks like a hole. It looks like tabs that broke their sealant strip and now lift in wind, letting rain drive underneath. From the ground the roof appears intact. This is the failure mode most often missed after a windstorm and most often caught in a post-storm inspection.
We would rather tell you a roof has eight good years left and fix a $600 vent boot than sell you a replacement you do not need. We would also rather tell you the truth when a repair is a stopgap. The honest dividing lines:
Repair makes sense when the damage is localized and the surrounding field is sound: an isolated flashing failure, a failed boot, storm damage confined to one slope, a valley that needs rebuilding. If the shingles still have flexibility, the granule loss is modest, and the deck under the damaged area is solid, a targeted repair is the correct financial decision.
Replacement is the honest answer when the failure is systemic rather than local: widespread granule loss exposing the asphalt mat, shingles that crack when lifted rather than flexing, multiple leaks in unrelated areas, soft or delaminated decking across more than a small patch, or an assembly already at or past its service life. Patching a roof in that condition buys months, not years, and every patch is money that does not count toward the replacement you will still be paying for.
There is also a real category of roof that is structurally fine but was installed wrong. Under-driven or over-driven nails, missing starter courses, no drip edge, valleys cut incorrectly. These roofs leak early and repeatedly, and the fix is corrective rather than cosmetic. Identifying that pattern early saves years of chasing symptoms.
Puget Sound windstorms arrive with the atmospheric river season, and the damage pattern is consistent: lifted and missing shingles on exposed slopes, ridge caps torn loose, branch strikes from bigleaf maple and Douglas fir, and gutter systems pulled off fascia by the weight of debris and water.
The first priority after a storm is not repair, it is stopping water intrusion without creating a second problem. A tarp fastened badly does real damage — screws driven through sound shingles into the deck create new penetrations that will leak long after the tarp is gone. Correct emergency tarping means running the material over the ridge where possible, securing at the edges with battens rather than field fasteners, and treating the tarp as a temporary dry-in that a permanent repair will remove cleanly.
Document everything before anything is disturbed. Photographs from multiple angles, dated, including interior damage, matter enormously for an insurance claim. If the damage is storm-related, the claim conversation and the repair conversation are two different processes, and starting the second before the first can cost you coverage.
Because water travels. After entering the assembly it runs along rafters, purlins, and sheathing until it finds a point where it can drip free, often fifteen or twenty feet from the entry point. This is why repairs aimed at the spot directly above a stain frequently fail.
Intermittent leaks usually point to wind-driven rain entering at a flashing or lifted shingle, or to condensation rather than a leak. We start in the attic reading water tracks, rule condensation in or out, then water test from the bottom of the suspect area upward in isolated stages with an observer inside.
Frequently, in Seattle. Warm moist indoor air reaching a cold attic condenses on the underside of the deck and produces staining that looks identical to a leak. The tells are moisture spread evenly across a whole slope rather than along a path, symptoms worse on cold clear nights than during rain, and bath or dryer vents terminating into the attic. The fix is ventilation and air sealing, not roofing.
Repair is the right call when damage is localized and the surrounding field is sound. Replacement is the honest answer when failure is systemic: widespread granule loss, shingles that crack instead of flexing, multiple unrelated leaks, or soft decking across more than a small patch.
Document everything with dated photographs from multiple angles, including interior damage, before anything is disturbed. Then stop the water intrusion with proper emergency tarping. Avoid tarps fastened with screws through sound shingles, which create new penetrations that leak long after the tarp is removed.
It is a small piece of flashing at the base of a roof-to-wall junction that redirects concentrated water into the gutter instead of behind the siding. It is frequently omitted, and when missing it channels water into the wall cavity where damage accumulates invisibly for years.
We measure in person, walk the roof, check the attic, and give you a written fixed quote — not a satellite guess.
