Damage Assessment
Chimney Flashing Damage After a Storm: Signs of a Leak
Chimney flashing is one of the most common places a roof starts leaking after a storm, because it's made of several separate metal pieces -- step flashing along the sides, counter-flashing set into the chimney masonry, and base flashing at the bottom -- any one of which can shift, crack, or separate from wind or debris without necessarily damaging the shingles nearby. Look for visible gaps or lifted metal at the roof-to-chimney joint, cracked or missing mortar where counter-flashing is set into the brick, and water staining on the ceiling or attic near the chimney, which is often the first sign something has failed.
Direct Answer
Chimney flashing is one of the most common places a roof starts leaking after a storm, because it's made of several separate metal pieces -- step flashing along the sides, counter-flashing set into the chimney masonry, and base flashing at the bottom -- any one of which can shift, crack, or separate from wind or debris without necessarily damaging the shingles nearby. Look for visible gaps or lifted metal at the roof-to-chimney joint, cracked or missing mortar where counter-flashing is set into the brick, and water staining on the ceiling or attic near the chimney, which is often the first sign something has failed.
What to check around your chimney after a storm
Chimney flashing leaks often develop gradually and aren't always visible from the ground, so a systematic check matters.
- Look at the step flashing along both sides of the chimney for any piece that looks lifted, bent, or displaced compared to the shingles around it.
- Check where counter-flashing meets the chimney's brick or masonry for cracked, crumbling, or missing mortar -- this is a common entry point once the flashing itself is no longer sealed tightly against the chimney.
- If the chimney is wide enough to have a cricket (a small peaked structure on its uphill side that diverts water around the chimney instead of pooling against it), check that it's still intact and properly sealed.
- Check the attic near the chimney chase for water staining, damp insulation, or a musty smell, since this can appear well before a visible ceiling stain shows up in a living space below.
- Note whether the flashing sealant looks cracked, chalky, or separated from the metal -- deteriorated sealant is a common failure point on its own even when the flashing metal itself is undamaged.
Why chimney flashing gets overlooked
- A chimney flashing leak can develop without any visible shingle damage nearby, since the failure is in the metal-to-masonry seal rather than the roofing material itself -- a quick drone-only or ground-level storm inspection can miss it.
- Because chimney flashing involves multiple separate components (step flashing, counter-flashing, base flashing, and sometimes a cricket), a repair sometimes only needs to address the specific failed piece rather than the whole assembly -- worth clarifying with your provider before assuming a full chimney flashing replacement is needed.
- Recurring leaks in the same spot after repeated attempted fixes often point to deteriorated mortar rather than the flashing metal itself, which needs a mason's repair, not just a roofer's.
Sources
The data above is cited directly from these publishers - follow the links to read the original reporting.
Frequently Asked Questions
Can a chimney flashing leak show up somewhere other than right next to the chimney?
Yes. Water can travel along roof decking or framing before showing as a stain, so a stain some distance from the chimney doesn't rule out flashing as the source.
Is chimney flashing repair usually cheaper than replacing the whole roof section?
Generally a flashing repair addresses just the affected metal and sealant, which is a smaller job than a broader roof section replacement -- but the exact scope depends on what your provider finds once they've inspected it closely.
Does homeowners insurance typically cover storm-caused chimney flashing damage?
Storm-caused flashing damage is often treated similarly to other storm damage to the roofing system, but coverage specifics depend on your policy -- confirm directly with your insurer or agent rather than assuming.