Chimney Flashing Repair Seattle, WA

Chimney flashing is the layered metal that bridges the joint where your chimney passes through the roof. It is the most common place a chimney leaks, and in the Seattle area it spends eight or nine months a year under steady rain. Chimney flashing repair means diagnosing exactly where water is getting past that joint, then resealing, reshaping, or replacing the step flashing and counter flashing so the roof and the chimney shed water together again. If you have a water stain on the ceiling near the chimney, damp drywall beside the fireplace, or rust streaks on the roof below the chimney, this is usually the service you need.

James Chimney Sweep repairs flashing on brick, block, and stucco-clad chimneys across King, Pierce and Snohomish counties along the I-5 corridor, from DuPont up to Mount Vernon. We handle the chimney side of the joint, and we are honest about when a problem actually belongs to a roofer instead.

Because flashing failures often show up only after a long wet stretch, the sooner the joint is inspected the less water ends up in the framing, insulation, and finishes below it.

Timing & Safety

When Flashing Repair Is Necessary vs. Optional

Necessary now:

• Active interior staining or dripping near the chimney after rain
• Metal visibly lifted, separated from the chimney, or missing
• Counter flashing that has pulled free of the mortar joint
• Rusted-through or pinholed flashing
• Wet insulation or sheathing in the attic next to the chimney

Worth doing soon, but can be scheduled:

• Sealant that is cracked or chalky but the metal still overlaps correctly
• Tar-only flashing that is not leaking yet but has no counter flashing
• A new roof going on, which is the ideal moment to re-flash the chimney

Repair vs. full re-flash threshold: if the metal itself is sound and correctly layered, a reseal or reset is usually the right call. If more than one side is failing, the metal is corroded, or the original job was tar and caulk with no proper step flashing, patching tends to buy a season at best and a full re-flash is the honest recommendation.

Safety considerations

Flashing work happens at the roofline, often on steep or slick Seattle roofs. Wet moss and algae make composition shingles and cedar shakes far more slippery than they look, and a fall from even a single-story roof can be serious. We do not recommend homeowners go on the roof to check or patch flashing; a technician with proper fall protection and roof-safe footwear handles the inspection and the work.

• Smearing roofing tar over a leak from the ground or a ladder often hides the problem and makes the proper repair harder later.
• Water that has been entering for a while can rot rafters and sheathing near the chimney, which is another reason not to walk that area yourself.
• If the chimney serves a gas appliance and you ever smell gas, leave the house and call your gas utility or 911 before anything else.

Seattle & Puget Sound conditions

Puget Sound weather is hard on flashing for three specific reasons. First, the sheer volume of rain from October through May means any small gap sees water constantly, not occasionally, so minor sealant failures become interior leaks quickly. Second, moss and fir needles collect in the uphill joint behind the chimney, holding water against the metal and masonry and wicking it under the shingles; a cricket and regular debris clearing matter more here than in drier climates. Third, the freeze-thaw cycles we get in cold snaps push open mortar joints that the counter flashing seats into, loosening the metal even when the sealant looks fine. Older Seattle and Tacoma homes also frequently have flashing that was never built with counter flashing at all, just tar, which was never a long-term answer in this climate.