Chimney Leaks in Kirkland: What Causes Them and How We Fix Them

A leaking chimney rarely fixes itself, and the water almost always enters from one of a few predictable places. Finding the real source — not just sealing the symptom — is the whole job, and it is what keeps a Kirkland chimney dry for good.

The cracked crown

The crown is the concrete slab on top of a masonry chimney, sloped to shed water away from the flue. When it cracks — from freeze-thaw, poor original construction or age — water pours straight into the masonry below and does slow, hidden damage all winter. We seal hairline cracks with a flexible weatherproof coating or rebuild a failed crown properly, with the slope and overhang it should have had.

Failed flashing

Flashing is the layered metal seal where the chimney passes through the roof, and it is the most common source of a chimney leak. Sealant dries and cracks, metal lifts or corrodes, or a reroof was done without properly re-flashing the chimney. We repair or replace it and seal it correctly so the joint sheds water again.

Porous brick and mortar

Brick and mortar are porous and soak up rain like a sponge. In an Illinois winter that trapped water freezes, expands and cracks the masonry apart. Once the brickwork is sound, a vapor-permeable sealant blocks rain while still letting the masonry breathe, stopping the freeze-thaw cycle that caused the damage.

Condensation and the liner

Not every “leak” is rain. A chimney venting a high-efficiency appliance can produce condensation inside an unlined or oversized flue, and that moisture mimics a leak. The fix there is proper liner sizing or a corrosion-resistant reline, not more sealant on the outside.

We trace it, not patch it

The mistake we see most in Kirkland is sealing over the symptom without finding the source, which just moves the problem. We track the leak to the crown, flashing, brick or liner and fix the actual cause. Water damage compounds fast, so a small, correctly-diagnosed repair now beats a rotted roof deck and stained ceilings later.

How we track down a hidden leak

Chimney leaks are deceptive because water travels. It can enter at the crown and show up as a stain several feet away, or run along framing before it drips. That is why we do not just reseal the nearest suspicious spot. We inspect the crown, the cap, the flashing and the masonry systematically, and where needed we test with water to confirm the true entry point before recommending a fix. Diagnosing the real source is what separates a repair that ends the leak from one that simply moves it. For a Kirkland homeowner, it is the difference between fixing it once and chasing it for years.

Published September 27, 2026 · Imperial Chimney Sweepers, DeKalb, IL