Chimney Crown - Sloped Top Surface of Masonry Chimney

A chimney crown is the sloped masonry or cement top surface that covers the top of a masonry chimney and sheds water away from the flue.

What It Is

The chimney crown sits at the top of a masonry chimney just below the chimney cap. Its job is to protect the chimney structure by directing water away from the flue opening and the outer chimney walls.

A properly built crown slopes away from the flue, projects beyond the chimney edges, and includes a drip edge. When the crown cracks, water can enter the masonry and accelerate brick, mortar, and liner deterioration.

Where It Is Used

Chimney crowns are used on masonry chimneys, not on framed chases for factory-built fireplaces. They are part of the weatherproof top detail of brick, block, or stone chimneys.

How to Identify One

From the roof, the crown is the solid top surface around the flue tile. It is often made of cementitious material and should slope away from the center. Cracks, spalling, missing overhang, and water stains below the chimney top are common warning signs.

Replacement

Minor cracks can sometimes be resurfaced with approved crown repair products, but badly cracked or poorly shaped crowns often need to be rebuilt. Lasting repair depends on restoring proper slope, overhang, and water shedding.