Common brick chimney problems and how they are repaired

Updated November 4, 2026 · First published April 5, 2024

Most brick chimney problems are caused by water: cracked or spalling brick, deteriorating mortar, a cracked crown, a missing cap, or loose flashing. The repair depends on which of these is letting water in.

Cracked or spalling brick

Chimneys are exposed on every side, so their brick goes through more wetting and freezing than most walls. Brick that cracks or loses its face should be replaced before water reaches the inside of the chimney.

Deteriorating mortar

Mortar joints on a chimney often fail before the brick does. Crumbling or recessed joints are repaired by tuckpointing.

Cracked crown

The crown is the sloped surface at the top of the chimney around the flue. Cracks in the crown let water directly into the chimney structure.

Missing or damaged cap

A chimney cap covers the top of the flue to keep rain, debris and animals out. Without one, rain falls straight down the flue.

Loose or damaged flashing

Flashing seals the joint between the chimney and the roof. When it loosens, rusts or pulls away from the brick, water runs down behind it and shows up on ceilings and walls next to the chimney.

Finding the right repair

Because a chimney leak can come from the brick, the top of the chimney, or the roof around it, the source should be found before any repair. See brick chimney repair, or call (219) 743-0451 for a free on-site evaluation.