Spokane winters bring repeated freeze-thaw cycles that expand and contract skylight frames, breaking old sealant beads and flashing joints on homes built before 1970 in neighborhoods like South Hill and Browne's Addition. These older houses often have curb-mounted skylights set into asphalt shingle roofs that were never designed for the heavy snow loads common in Spokane County. We inspect the flashing, curb, and underlayment first because surface caulk alone fails when meltwater finds the gaps created by decades of movement.
Proper sealing requires removing failed material down to the roof deck, installing new step flashing integrated with the existing shingles, and applying high-grade polyurethane or butyl tape rated for extreme temperature swings. In Spokane Valley and surrounding areas, wind-driven rain during spring storms can push water under poorly lapped flashing, so we always extend the new flashing at least six inches up the curb and overlap it correctly with the roof plane. Homeowners often mistake attic condensation for skylight leaks, but we verify by checking for actual water stains on the ceiling and testing the seal during wet weather.
Access on Spokane's steeper roof pitches common in the Perry District requires proper staging and fall protection, and we never rely on roof tar alone because it cracks within one season under UV and snow. We also check the skylight glazing itself for cracked seals between the glass and frame, which is a frequent secondary leak path on units installed twenty or more years ago.
After sealing we run a controlled water test from the ridge down to confirm no new paths open, then document the work with photos for the homeowner. This approach addresses the root causes rather than just the visible drip.
Technician insight
In Spokane the thing that catches most people out with skylight leak sealing is assuming the drip is only at the glass when the real failure is usually the step flashing lifting from decades of snow load and ice dams on South Hill roofs. We see this constantly on pre-1960 homes where the original curb was never flashed correctly for our freeze-thaw winters.
South Hill Skylight Leak After Heavy Snow
Water stains appeared on the ceiling of a 1950s Spokane home after a series of heavy snowfalls followed by rapid melt. We found lifted flashing and cracked sealant at the skylight curb where snow had pushed under the laps. New step flashing was installed and the curb was resealed with temperature-rated material, stopping the leak before interior damage spread.
Skylight Leak Sealing Services We Offer
✓Skylight Flashing Replacement
Removes corroded or lifted step flashing around the skylight curb and reinstalls new metal flashing integrated with the roof shingles to stop water entry in Spokane snow conditions.
✓Curb Sealant Renewal
Cuts out degraded polyurethane or butyl sealant at the skylight frame and applies fresh, UV-stable sealant rated for Spokane's freeze-thaw cycles.
✓Skylight Curb Repair
Rebuilds damaged or rotted wood curbs on older Spokane homes before resealing to restore a solid base that prevents future leaks.
✓Underlayment Patch at Skylight
Replaces torn or missing ice-and-water shield and felt underlayment around the skylight opening to restore secondary protection against Spokane rain.
✓Skylight Glazing Reseal
Addresses failed seals between glass and frame on aging skylights common in Spokane County homes, stopping interior condensation and drip paths.
Skylight Leak Sealing Cost in Spokane, WA
| Service | Typical Range | What Affects It |
|---|---|---|
| Single skylight sealant refresh | $250–$450 | Minor surface work on accessible low-slope roofs |
| Skylight flashing replacement | $600–$950 | Includes new metal flashing and integration with shingles |
| Curb rebuild plus sealing | $850–$1,400 | Wood repair needed on older Spokane homes |
| Multiple skylights on same roof plane | $1,100–$2,200 | Discounted when work is done together |
Ranges are typical for Spokane, WA and confirmed with an exact written quote before any work starts.
How it works
- 1
Inspection and Diagnosis
We examine the skylight from both attic and roof, checking flashing, sealant, and underlayment for damage caused by Spokane snow and temperature swings.
- 2
Material Removal
Old sealant and compromised flashing are removed down to sound substrate without disturbing the existing roof more than necessary.
- 3
Flashing and Sealant Installation
New step flashing is woven into the shingles and a fresh curb seal is applied using materials suited to Spokane winters.
- 4
Water Testing and Cleanup
A controlled water test confirms the repair, followed by site cleanup and photo documentation for the homeowner.
Pricing
Cost depends on roof pitch, number of skylights, and extent of underlying damage; we provide upfront quotes after inspection.