Chimney Flashing and Roof Leaks in Paw Paw

If you have a water stain on the ceiling near the chimney, the flashing is the first suspect. It is the most common source of a chimney-related roof leak, and diagnosing it correctly saves a Paw Paw homeowner from chasing the wrong repair.

What flashing does

Flashing is the layered metal seal where the chimney passes through the roof. Done right it is a two-part system: step flashing woven into the shingle courses along the sides, and counter flashing set into the masonry above, overlapping the step flashing so water is channeled away from the joint at every level.

Why it fails

Flashing fails for predictable reasons: sealant dries out and cracks, the metal lifts or corrodes, the roof and chimney move at slightly different rates over the years, or — very commonly — a reroof was done without properly re-flashing the chimney. The result is a leak that looks like a roof problem but is really a chimney one.

How to tell it’s the flashing

Flashing leaks typically show up as stains on the ceiling or wall right around the chimney, and they often worsen with wind-driven rain. Because the water can travel along framing before it drips, the stain is not always directly below the entry point — which is exactly why a careful diagnosis beats guessing.

The fix

We repair or replace the flashing and seal it correctly so the joint sheds water again. Where a reroof left the old flashing in place, we install a proper two-part system. And where the leak has already reached the masonry or the interior, we address that damage too rather than sealing over it.

Don’t wait on a leak

Water damage compounds. A small flashing repair now beats a rotted roof deck, stained ceilings and interior masonry damage later. If you see a stain near the chimney in your Paw Paw home after a hard rain, have it looked at before the next storm makes it worse.

After a new roof, check the chimney

One of the most common flashing failures we see follows a roof replacement. Roofers sometimes reuse or reseal old chimney flashing rather than installing a proper new two-part system, and the leak shows up a season or two later. If you have had your Paw Paw roof redone, it is worth confirming the chimney was correctly re-flashed — step flashing woven into the shingles and counter flashing set into the masonry above. Catching a shortcut early, before water reaches the decking and framing, saves an expensive repair that has nothing to do with the shingles themselves.

Published October 11, 2026 · Imperial Chimney Sweepers, DeKalb, IL