Spokane winters bring repeated freeze-thaw cycles that expand and contract metal flashing, loosening seals around chimneys and pipe penetrations. Older homes in neighborhoods like Browne's Addition and the South Hill often have original lead or copper flashing that has corroded after decades of exposure. Proper replacement requires matching the existing roof slope and using compatible materials such as galvanized steel or aluminum with high-grade butyl tape to handle the temperature swings common in Spokane County.
Edge cases appear at valley intersections and dormer walls where improper overlap lets snowmelt run behind shingles. In Spokane, wind-driven rain from the east can push water under step flashing if the counter-flashing is not tucked correctly into masonry joints. Technicians must also account for the steep pitches found on many pre-1950 houses and ensure new sealant remains flexible below 20 degrees without cracking.
Code compliance in Spokane requires flashing to extend at least six inches up vertical surfaces and under the roof membrane. Homeowners frequently discover issues only after water stains appear on ceilings near bathroom vents or kitchen exhausts. Addressing these points during re-roofing prevents callbacks and keeps interior damage from spreading through the older plaster and lath common in the area.
Technician insight
In Spokane, the thing that catches most people out with flashing and sealing is the way freeze-thaw cycles on South Hill roofs push water under step flashing that still looks tight from the ground. Homeowners often wait until interior stains show up because they assume the metal is fine, yet the sealant has already cracked after two or three winters.
South Hill Chimney Leak
Water stains appeared on a second-floor ceiling after heavy March rain. Inspection found cracked sealant and lifted step flashing on a 1920s brick chimney. New galvanized flashing was installed with fresh butyl tape and counter-flashing tucked into the mortar joints. No further leaks occurred through the next winter.
Flashing and Sealing Services We Offer
✓Chimney Flashing Repair
Replaces deteriorated step and counter flashing around brick chimneys to stop leaks common after Spokane freeze-thaw cycles.
✓Skylight Sealing
Removes old sealant and installs new flashing kits plus high-quality caulk to prevent water entry at skylight curbs.
✓Valley Flashing Replacement
Installs new metal valley flashing with proper overlap and sealant to handle heavy spring runoff in Spokane.
✓Vent Pipe Sealing
Reseals boot flashings around plumbing and HVAC vents using ice-and-water shield and compatible mastic rated for cold temperatures.
✓Dormer Wall Flashing
Repairs or upgrades step flashing at dormer walls where wind-driven rain often penetrates older Spokane homes.
Flashing and Sealing Cost in Spokane, WA
| Service | Typical Range | What Affects It |
|---|---|---|
| Chimney flashing repair | $350–$750 | Price varies with chimney height and whether masonry tuck-pointing is needed. |
| Skylight reseal | $200–$450 | Higher when custom flashing must be fabricated on site. |
| Valley flashing section | $150–$400 | Depends on length and whether shingles must be lifted. |
| Multiple vent boots | $180–$350 | Per three to five vents; access difficulty on steep roofs increases cost. |
Ranges are typical for Spokane, WA and confirmed with an exact written quote before any work starts.
How it works
- 1
Inspection
Technician climbs the roof and checks all transition points for rust, gaps, and failed sealant while noting roof age and slope.
- 2
Material Selection
Chooses flashing type and sealant rated for Spokane winter lows, confirming compatibility with existing shingles or metal.
- 3
Removal and Prep
Carefully removes old flashing without damaging surrounding roofing and cleans surfaces to ensure new materials adhere.
- 4
Installation
Installs new flashing with correct overlaps, tucks counter-flashing into masonry where needed, and applies fresh sealant.
- 5
Final Check
Walks the roof again, tests drainage at valleys, and confirms no exposed fasteners remain before leaving the site.
Pricing
Most flashing and sealing jobs in Spokane fall between a few hundred and low thousands depending on access and extent.