Herscher farmhouse chimney leak that soaked the attic: it was the flashing, and the missing cricket
A Herscher homeowner had a water stain spreading across the ceiling near the chimney and a roofer who could not find the leak. The chimney was sound. The problem was where the roof met the brick.
A wet ceiling near a dry chimney
The brick was in good shape and the crown was intact, so the homeowner assumed the roof was failing. But the stain always appeared on the uphill side of the chimney after a driving rain. That pattern points straight at the flashing — the layered metal that seals the gap where the roof plane meets the masonry. On the rural farmhouses around Herscher, with their steep older roofs and wide masonry stacks, this is the leak we find most.
Flashing has two parts: step flashing woven into each course of shingles, and counterflashing let into the brick joints over the top of it. When either lifts, rusts, or was only caulked in place, water runs behind it and into the deck.
The missing piece: a cricket behind a wide chimney
This chimney was wide and sat partway down the roof slope. On the uphill side, rain and — in our winters — snowmelt had nowhere to go but to pool against the brick. A chimney more than about two feet wide on the high side of a roof needs a cricket, a small peaked saddle that splits the water and sends it around each side. This one never had one. Water sat against the flashing every storm until it found a way in.
Building a cricket and tying new step and counterflashing into it is the permanent fix. A bead of roof cement over old flashing is not — it cracks within a season or two and the leak comes back worse because now the sheathing is already soft.
How we repair it to last
We cut fresh reglets into the mortar joints for the counterflashing so it is mechanically locked into the brick, not glued to the face. We weave new step flashing with the shingle courses and frame and flash the cricket so the water divides cleanly. Where the deck had rotted, we flagged it for the homeowner so the roofer could replace the soft sheathing before we closed it up — the two trades have to meet here.
If you have a stain that only shows after wind-driven rain, do not keep patching the ceiling. Find the joint. Our repair pricing is published, and we are insured and bonded for work on the roof.
If this sounds like your house: we handle chimney repair across Kankakee County, and our Herscher page covers what we usually find there. Call (815) 449-4264, 7am to 9pm, any day.
Quick questions
How do I know if my chimney leak is flashing and not the roof?
Flashing leaks usually show up only after wind-driven rain and appear right at the chimney, often on the uphill side. A failing roof tends to leak more generally. A camera and a close look at the roof-to-brick joint tell us which it is.
What is a chimney cricket and do I need one?
A cricket is a small peaked saddle built behind a chimney on the high side of the roof to divert water around it. A chimney wider than about two feet on the uphill side generally needs one, or water pools against the brick.
Can’t I just caulk the flashing?
Caulk and roof cement are temporary. They crack within a season or two and the leak returns, usually after the sheathing has already softened. Proper flashing is metal locked into the mortar joints and woven into the shingles.
Do you work with my roofer on the repair?
Yes. If the roof deck is rotted from a long-running leak, that’s the roofer’s part. We flag it, flash the masonry side correctly, and coordinate so the joint is sealed by both trades.
Published November 5, 2026 · By Jacob Dove, Friendship Chimney Sweep, Bourbonnais IL