Smoke Backing Up Into the House: If smoke is not venting properly through the chimney and is entering your living space, it may be blocked or have a buildup of creosote. Cracked or Missing Bricks: Cracks in the masonry or missing bricks can indicate structural issues and water damage to the chimney. Rust on the Damper or Firebox: Rust in these areas can signify moisture issues, whic... https://www.housetriangle.com/