Chimney Crown Repair in New Jersey

What the crown does

The crown, sometimes called the wash, is the cap of mortar or concrete that covers the top of the masonry and surrounds the flue tile. It should slope away from the flue and overhang the brick below so rain runs off and drips clear of the walls of the chimney.

It is the most exposed part of the chimney, and a cracked crown is one of the most common ways water gets into a chimney. A crown is not the same thing as a chimney cap, which is the metal cover over the flue opening.

Signs of a failing crown

• Cracks across the top, from hairline to wide
• Crumbling, flaking or sandy surface
• A gap between the crown and the flue tile
• Standing water or stains on the crown
• Damaged brick or mortar just below the crown
• White powder (efflorescence) on the upper brick
• Water stains inside the house near the chimney

Why crowns fail

Water gets into small cracks, freezes, and widens them. That cycle repeats every winter. Many crowns also fail because of how they were built: a thin layer of ordinary mortar instead of a proper concrete slab, little or no overhang, or no flexible joint where the crown meets the flue tile. The flue tile and the crown expand and shrink differently, and a rigid joint between them tends to crack.

How we look at it

We check the crown surface, the joint at the flue tile, the overhang and the condition of the masonry below. The question is whether the crown can be repaired or needs to be rebuilt, and whether water is already getting into the brick.

Repair or rebuild?