ChimneyFlashing
Four Sides, Zero Shortcuts

You often can’t from inside — flashing, crown and brick leaks all stain the same ceiling. The water test on our leak repair page separates them before money moves.

It is the cap layer set into the mortar itself, lapping over the step flashing so water running down the brick face lands on metal, not behind it. Skipping it is the classic shortcut.

The surrounding shingle courses lift and re-lay as part of the job — another reason this is roofer metalwork, not a caulk-gun visit.

Age, movement between roof and masonry, and generations of tar smeared over the original problem — the black goop era traps water against brick while hiding the failure.

A small peaked diverter behind the stack that splits water around it — generally recommended (and often required) for chimneys more than two feet wide.

Sealant has a small finishing role at counter-flashing edges — as the whole strategy, it’s the tar-cycle trap. The system is metal; caulk is a detail.

Aluminum and galvanized serve well; copper is the buy-once-cry-once option that outlasts everything around it. Compatibility with masonry and budget decide.

Counter-flashing cut into mortar joints (not surface-glued), woven steps at the sides, and a cricket behind wide stacks — three glances that grade most installs.