Chimney anatomy

01 · Chimney cap

A chimney cap sits on top of the chimney to prevent rain, debris, and animals from entering.

• Can become damaged or blown off in strong winds
• May rust or deteriorate over time
• Screens can get clogged with creosote or debris

02 · Crown

The crown is a slab, usually made of cement, that covers the top of the chimney to protect it from weather.

• Cracks can form due to weather exposure
• Improper slope can cause water pooling
• Deterioration from freeze-thaw cycles

03 · Flashing

Flashing is the metal layer that seals the joint between the chimney and the roof to keep water out.

• May become loose or corroded
• Water leaks can occur if not sealed properly
• Flashing can separate from the chimney or roof

04 · Brick and mortar

Brick and mortar make up the structure of the chimney, providing stability and a pathway for smoke.

• Mortar joints can crack or crumble
• Bricks can spall or crack
• Water penetration leading to deterioration

05 · Flue liner

The flue liner is a conduit inside the chimney that safely directs smoke and gases out of the home.

• Cracks can form, allowing gases to leak
• Creosote buildup can occur
• Improperly sized liners reduce efficiency

06 · Smoke chamber

The smoke chamber guides smoke from the firebox into the flue, helping improve draft.

• Parging (smooth coating) can degrade
• Improper construction leads to poor draft
• Creosote and soot accumulation

07 · Damper

A damper is a moveable plate that seals off the chimney when not in use, preventing heat loss.

• Can become stuck or difficult to operate
• May not seal properly, allowing drafts
• Old dampers might rust and deteriorate

08 · Firebox

The firebox is where the fire burns, built to contain heat safely in the fireplace.

• Bricks or panels can crack from heat
• Mortar joints can deteriorate over time
• Metal parts may rust or warp