Flashing is the interlocked metal that waterproofs the joint between a chimney and the roof it passes through, and it is the number-one answer to the county's most common chimney question: why is there a brown stain on the ceiling next to the fireplace? When step flashing rusts, counterflashing pulls out of its mortar joint, or a previous owner's tar smear finally gives up, every rain finds the framing. A local chimney mason covering Cleveland, Cleveland Heights, Parma, and the rest of Cuyahoga County calls back with a free estimate.
How flashing is supposed to work, and how it fails here
Done right, it's a two-layer system: step flashing woven into the shingle courses and turned up the brick, then counterflashing let into a cut mortar joint and folded down over the steps, so water crossing the roof can never reach a vertical seam. Cuyahoga County breaks it in predictable ways. Ice dams — the thick shelves that build at the eaves and around stacks in the snow belt from Euclid up through the Heights — back meltwater uphill under the shingles and over the top of tired flashing. Freeze-thaw opens the mortar joint holding the counterflashing until the metal hangs loose. Galvanized steel from mid-century installs simply rusts through. And on more roofs than anyone would like, the "flashing" is a decade of roofing cement troweled on in layers, each one cracking a little sooner than the last. Tar over tar is not a repair; it's a subscription.
What the repair looks like
Where the metal is sound and the mortar joint has failed, the counterflashing is re-let: the joint ground clean, the metal reset, and the reglet sealed. Where the steps have rusted or were never woven correctly, the shingle courses beside the stack come up and new step flashing goes in piece by piece — on the county's older slate and tile roofs in the Heights, that's careful work with matching fasteners, and the mason will say so rather than walk on slate carelessly. Where nothing under the tar is salvageable, the whole assembly is refabricated in new metal. A saddle — the small peaked cricket behind a wide stack — gets added where snow piles against the uphill face, which is standard prescription for the broad chimneys on Lakewood doubles and old four-squares.
The honest boundary with the roofing trade
Flashing is the seam between two trades, and this site keeps the seam honest. The chimney side — the counterflashing, the reglet, the masonry it anchors to, the stack itself — belongs to the masons on this roster. A roof that is failing beyond the flashing — shingles at end of life, decking gone soft, gutters feeding the ice dams — is a roofer's job, and the callback will say that instead of quoting chimney work as a bandage on a roof problem. Often the leak is not the flashing at all but the crown above it or saturated masonry that wants the leak-diagnosis approach; sorting that out from the symptoms you describe is what the free estimate is for. Photos from the ground — the stain inside, the stack outside — sharpen the number before anyone climbs.