Owens Corning Flashing Replacement: The Seattle Owner’s Guide
Owens Corning flashing replacement in Seattle typically runs $340-$780 installed, depending on the location and whether we’re working around dormers, chimneys, or wall transitions. We stock Owens Corning-compatible flashing profiles on every truck, and most replacements are completed in a single visit. Homeowners usually spot trouble after a hard November rain when water stains appear on ceiling corners or paint starts bubbling near where the roof meets a vertical surface.
Which Owens Corning Models This Applies To
Owens Corning doesn’t manufacture its own dedicated flashing line, but their Total Protection Roofing System specifies certain metal gauges, bend profiles, and corrosion-resistant coatings that must mate correctly with their shingles. If your roof was installed as an Owens Corning system between 1995 and today, the flashing was likely sourced to their spec: 26-gauge minimum galvanized steel or 0.019-inch aluminum, with a baked-on finish matching their Duration or Oakridge color palettes.
Here’s how to identify what you’ve got. Check the eave or rake edge for an Owens Corning logo stamp on the shingle bundle wrapper, or look for a system warranty certificate. The critical detail is the step-flashing profile at wall intersections: Owens Corning systems typically use 8-by-10-inch step flashings with a 2-inch wall leg and 4-inch exposure, though homes in Seattle’s older neighborhoods like Wallingford or Capitol Hill sometimes show 7-by-7-inch legacy sizes from pre-2000 installs. The wrong bend angle traps water behind cedar siding or HardiePanel, which is why we measure on-site rather than guessing from a photo.
We carry both OEM-spec flashing and quality aftermarket equivalents from Gibraltar and Amerimax that meet Owens Corning’s corrosion-resistance standards. For homes within two miles of Puget Sound, we spec heftier 24-gauge or Kynar-coated aluminum. The salt air in neighborhoods like Alki or Magnolia eats standard galvanized in half the time.
Signs Your Owens Corning Flashing Replacement Is Failing
- Water stains on interior ceiling corners. The step flashing at a wall-roof intersection has lifted, separated, or rusted through, letting wind-driven rain channel directly into the framing. In Seattle’s south-wind storms, this shows up first on the north-facing walls.
- Bubbling or peeling paint on exterior walls below the roofline. Capillary action is pulling moisture behind the siding because the counterflashing seal has failed or the kick-out diverter was omitted. We see this constantly on 1980s split-levels in Northgate where original installers cheaped out on the diverter.
- Granule accumulation in gutters below valley intersections. The valley flashing has buckled or the W-profile has cracked at the center seam, allowing shingles to shift and shed granules. Owens Corning systems with open valleys are especially prone if the ice-and-water barrier wasn’t run 18 inches up each slope per spec.
- Visible rust streaks on chimney brick or siding. The base flashing has corroded at the mortar joint or the saddle cricket flashing has split at the solder seam. Galvanized steel in Seattle’s moss-friendly climate typically shows this in 12-18 years, not the 25-year shingle warranty.
- Daylight visible from the attic at pipe or vent penetrations. The rubber collar on a pipe boot has cracked, or the adjustable flashing base has slipped out of position. Owens Corning systems use standard 3-inch or 4-inch pipe boots, but the critical detail is whether the flange was bedded in mastic or left dry, which determines if we can reuse the surrounding shingles.
Replacement Cost & What’s Included
| Flashing Type | Typical Range (Seattle) | What Drives Price |
|---|---|---|
| Step flashing (wall intersection, per linear foot) | $28-$45 | Stucco or brick removal/replacement, siding type |
| Chimney base and counterflashing | $340-$680 | Height, accessibility, cricket rebuild needed |
| Valley flashing (open or closed) | $420-$780 | Length, shingle removal and reinstallation |
| Pipe boot replacement | $180-$290 | Pipe diameter, attic access, surrounding shingle condition |
| Dormer cheek flashing | $380-$620 | Dormer size, window integration, wall cladding |
These prices include removal of failed material, installation of new flashing to Owens Corning system spec, replacement of any damaged underlayment, and reinstallation of surrounding shingles with matching products from our GAF, CertainTeed, or Owens Corning inventory. We don’t quote over the phone without seeing the roof. The number on our estimate is the number on your invoice. Every flashing job carries our 90-Day Done Right Promise: if water gets through, we come back and make it right, no paperwork, no arguing.
DIY or Call Us?
There’s a safe middle ground here. You can check your attic during daylight for the symptoms above, and you can trace interior stains to their approximate roof origin. That’s useful information to share when you call.
But flashing work means working at height on a slope, removing shingles without tearing them, and bending metal to fit irregular intersections without leaving gaps. The bend radius on step flashing matters: too tight and it cracks; too loose and it tents. Seattle’s frequent drizzle makes every surface slicker than it looks. We’ve responded to enough DIY falls and botched caulk jobs to say plainly: this is trained work. Our background-checked, uniformed technicians carry the brake tools, seamers, and color-matched stock to finish in one visit. Call (866) 850-9676 and a live person will pick up, 24/7, including the middle of a January storm.
FAQs
Properly installed galvanized flashing in Seattle’s climate typically lasts 15-20 years; aluminum or Kynar-coated products reach 25-30. Moss retention, proximity to salt air, and whether the original installer used compatible metals (never copper against steel) are the deciding factors. Call (866) 850-9676 for an exact assessment of your system.
Small separations at a seam can sometimes be re-soldered or sealed with compatible urethane, but rust, cracks, or lifted profiles mean replacement. Patching over failed flashing wastes money: the water’s already found the path. We offer free estimates so you know which category you’re in.
Most single-area flashing replacements are completed in 2-4 hours. Chimney work or full valley runs may extend to a full day. We photo-document before and after, and we don’t leave until the site is clean and the roof is watertight.
We stock Owens Corning-compatible step flashing, valley metal, pipe boots, and chimney components in standard Seattle profiles and colors. For custom architectural details or discontinued color matches, we fabricate or source within 24-48 hours. Same-day completion is standard for common configurations.
Ridgeline Roofing Co. of Seattle is an independent service provider. We are not affiliated with Owens Corning, though we are authorized to install their products and maintain their system specifications.
Written by Neil Cavanaugh, Owner, Ridgeline Roofing Co. of Seattle at Ridgeline Roofing Co. of Seattle, serving Seattle and nearby areas.