Top Flue Tile

The top flue tile is the last section of the clay flue liner, the part that sticks up above the chimney crown. It is the outlet where smoke leaves the chimney, and it usually supports the chimney cap or a top-sealing damper. Because it is fully exposed to the weather and to the heat of the exhaust, it is one of the first parts of a chimney to wear out.

As the checklist above shows, the top tile should extend a few inches above the crown, and there should be room around it for the tile to expand when it heats up. When a crown is poured tight against the tile with no room for movement, the tile can crack as it heats and cools, and the crown often cracks along with it.

• Cracks, chips, or missing pieces at the top of the tile
• A tile that is loose, tilted, or shifted on the crown
• Gaps between the tile and the crown, or a crown cracked around the tile
• Pieces of clay tile falling into the firebox or collecting at the clean out
• A chimney cap that won’t sit securely on the tile
• Water or rust inside the fireplace after rain

Most of these are only visible from the roof, which is why the top of the chimney is part of every inspection we do.

Inspect. We look at the tile, the crown, and the cap, and check the liner below for further damage. If the damage continues down the flue, we’ll explain relining options.

Replace the top tile. When only the top tile is damaged, it can often be removed and replaced with a new tile of the right size, set in proper mortar with full joints.

Fix the crown connection. We repair or rebuild the crown around the new tile, leaving space for expansion and sealing the gap with a flexible, heat-rated sealant instead of locking the tile in solid.

Cap it. A properly sized chimney cap keeps rain off the tile and out of the flue. For a tighter seal when the fireplace is not in use, a top-sealing damper can mount on the tile.

A cracked top tile lets water into the space between the liner and the chimney walls, where it soaks the masonry and damages the liner further down. Broken pieces can fall and partly block the flue. And because the liner is what keeps heat and smoke inside the chimney, a damaged tile weakens the whole system. Repairing the top tile early is usually much simpler than relining the chimney later. If water is already getting in, see chimney waterproofing and leak repair.