Chimney anatomy

01 · Chimney cap

A chimney cap sits at the top of the chimney, preventing rain, debris, and animals from entering.

• Corrosion or rust can lead to leaks.
• Clogs from debris buildup.
• Deterioration or damage from storms or wind.

02 · Crown

The crown is the top surface of the chimney that sheds water to protect the masonry below.

• Cracks can allow water to seep in.
• Crowning can wear down over time.
• Improper construction may lead to leaks.

03 · Flashing

Flashing is the metal layer that seals the joints between the chimney and the roof.

• Leaks caused by rusting.
• Improper installation may lead to gaps.
• Weather can wear it down, causing leaks.

04 · Brick and mortar

The brick and mortar make up the structure of the chimney, providing stability and support.

• Cracks or gaps from settling or freezing.
• Deterioration from moisture.
• Discoloration or efflorescence from water damage.

05 · Flue liner

The flue liner channels smoke and gases out of the house safely.

• Cracking or spalling that compromises safety.
• Corrosion from acidic gases.
• Improper sizing reducing efficiency.

06 · Smoke chamber

The smoke chamber funnels smoke from the firebox into the flue.

• Creosote buildup restricting airflow.
• Cracks that can leak smoke into the home.
• Improper shape affecting draft efficiency.

07 · Damper

The damper seals the chimney when not in use, preventing drafts.

• Rust or warping that affects movement.
• Improper closure leading to energy loss.
• Seals that can become worn, allowing drafts.

08 · Firebox

The firebox is where the fire burns in the fireplace.

• Cracked bricks or mortar joints.
• Wear from heat weakening the structure.
• Accumulation of ash reducing efficiency.