Sound chimney flues restored in Stoneybrook East

Using a smoke test to find leaks

When the question is whether a flue leaks, a smoke test can help. The flue is filled with test smoke while the top is covered, and we watch for smoke appearing where it should not, such as another flue, the attic or a room next to the chimney.

A smoke test shows that a leak exists and roughly where. It does not measure how large a crack is or show its exact shape. We use it when the visual evidence leaves the question open, and we explain what the result does and does not prove.

Listed lining systems and UL 1777

Among the lining options in Section R1003.11.1 of the Florida residential code are listed and labeled chimney lining systems complying with UL 1777. UL 1777 is the safety standard such systems are tested against, and the listing states what they may be used for.

When a repair product is offered as a lining for your flue, ask whether it is part of a listed system and what the listing covers. We name the product and its listing in your estimate, so you know exactly what is going into the chimney and why it qualifies.

Tiles that have shifted out of line

When a tile slides out of alignment with the one below it, a ledge forms inside the flue. The ledge catches deposits, disturbs the draft and often leaves an open joint on the other side.

Shifted tiles are usually a sign that the lining has lost support somewhere. We look at how far they have moved and whether a local repair is realistic, or whether the displacement points toward relining. Movement of a single tile at the top can sometimes be corrected when that section is reset. Movement lower down, or across several sections, usually cannot be reached without relining or opening the chimney wall.

What a flue repair estimate should list

A flue repair estimate should be specific enough to compare with another quote. Vague lines such as repair liner leave you unable to tell what is being fixed.

Ours list each item below. Book within 72 hours after the inspection and 10% off is printed right on the estimate.

• Sections of the flue included in the repair
• The method and the named product or material
• Cleaning and preparation before the repair
• Related work such as a cap, crown or cleanout cover
• Curing time and when the fireplace can be used
• Anything that could not be seen or confirmed