Chimney anatomy

01 · Chimney cap

The chimney cap sits at the very top of your chimney and helps keep rain, debris, and critters out.

• Rust or corrosion can cause the cap to deteriorate over time.
• Strong winds or storms can dislodge the cap.
• Clogging from leaves and debris can block airflow.

02 · Crown

The crown is a slab that covers the top of the chimney, sealing the area between the flue and the chimney edge.

• Cracking due to weather exposure can lead to leaks.
• Poor construction may cause it to degrade quickly.
• Water pooling on the surface may lead to further damage.

03 · Flashing

Flashing is the metal barrier that prevents water from seeping into the joint between the chimney and roof.

• Corrosion or rust can cause leaks.
• Shifting or settling of the house may create gaps.
• Improper installation might lead to immediate issues.

04 · Brick and mortar

The masonry structure of your chimney is made up of the bricks and mortar that form the chimney’s body.

• Mortar joints can crack or erode over time.
• Bricks may spall if moisture gets trapped and freezes.
• Algae or moss growth can damage the surface.

05 · Flue liner

The flue liner protects the chimney walls from heat and corrosion, and helps vent smoke and gases out of the home.

• Cracks can develop from heat or improper installation.
• Corrosion from acidic byproducts can erode it.
• Blockages from soot or creosote can restrict airflow.

06 · Smoke chamber

The smoke chamber is located just above the firebox and directs smoke into the flue.

• Rough surfaces can cause turbulence and restrict airflow.
• Cracks may develop due to heat stress.
• Build-up of creosote can occur over time.

07 · Damper

The damper is a movable plate that closes the flue to conserve energy when the fireplace is not in use.

• Rust or corrosion can make it difficult to operate.
• Improper sealing can lead to drafts or heat loss.
• Warping from heat exposure may prevent a proper seal.

08 · Firebox

The firebox is the chamber where the fire burns, encased in heat-resistant materials.

• Cracks in the refractory mortar or bricks can occur over time.
• Spalling from heat can damage the firebox surface.
• Improper ventilation can lead to smoke issues.