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The Sterling Chimney Sweep teamCan a cracked chimney flue tile be repaired?
Sometimes a small gap at a joint can be sealed, but a cracked or missing tile usually means relining the flue. Cracked clay tile cannot be made whole again, so the lasting fix is a new sealed channel inside the old one. A camera look tells you which case you have.
Why do flue tiles crack?
Clay tile is stiff, and a flue heats and cools every time you burn. Moisture gets in and freezes, a chimney fire can crack tile outright, and the chimney can shift over the years. Tile that has cracked no longer holds smoke, heat and gas inside the flue.
Why does it matter?
The flue exists to keep heat, smoke and carbon monoxide inside a sealed channel. When tile cracks, those can reach the brick and the wood framing nearby. That is why a cracked tile is a problem to settle before the next fire, not a cosmetic one.
What can be done about it?
| What we find | What it means | Usual route |
|---|---|---|
| A small gap at one joint | Mortar between tiles has worn | A sealant made for flues may do |
| A crack through one tile | The tile no longer holds | Relining |
| Missing or broken pieces | The flue wall has gaps | Relining |
| Cracks along several tiles | The whole flue is worn or damaged | Relining the full height |
What does the camera show you?
A camera on a flexible rod travels the flue from top to bottom. It shows each tile and each joint on a screen, so you see what we see. We take a photo of any crack or gap and explain where it sits in the flue. That is how you tell a small joint problem from damage that runs the full height.
What you can check safely
- Look in the firebox and on the smoke shelf for pieces of clay tile.
- Notice any smoke smell in rooms near the chimney when the fireplace is cold.
- Remember whether there was a chimney fire or a loud pop in the chimney.
Stop and call: do not light the fireplace if you find tile in the firebox. A carbon monoxide alarm that sounds means going outside and calling 911. If anything in the chimney is burning, get everyone out and call 911 first.
How do you find out for sure?
Only a look inside the flue shows tile condition, which is why a Level 2 inspection always includes a camera. Relining the flue puts a new sealed channel inside the old tile. Owners in Shoreview and Arden Hills can book the same camera look.
Flue tile questions
Short answers first.
Is a cracked chimney liner dangerous?
It can be. Heat, smoke and gas can pass through the crack toward the framing or into the house. Hold off on burning until it has been looked at.
How would I know a tile is cracked?
Pieces in the firebox or a smoky smell can hint at it. The only sure way to see it is a camera scan of the flue.
Do you fix one tile or the whole flue?
It depends on what the camera shows. A single sealed joint is a small job. Damage in several places points to relining the whole flue.
Found clay pieces in the firebox?
Keep the fireplace unlit and give us a call. We will plan a camera look inside the flue.