Damaged chimney flues repaired in Lockhart

Flue size for an open fireplace

Open fireplaces need a flue large enough for the size of the fireplace opening. The Florida residential code sets fireplace flue sizing in Section R1003.15, and BIA Technical Note 19B treats flue area and chimney height as the two most critical factors in how a chimney performs.

A repair should not quietly shrink a fireplace flue below what the opening needs. When a proposed method would reduce the inside area, we say so and explain how that might affect draft, before you choose it.

When resurfacing is the wrong answer

Resurfacing works on a flue that is still in position and mostly intact. It is not a cure for missing tile sections, tiles that have slipped out of line, liners that have lost support or sharp offsets that cannot be reached evenly.

When we see those conditions, we say so and do not offer resurfacing just because it sounds simpler. The alternatives, usually local tile replacement or a new liner, are explained in writing so you can compare them fairly.

Repair or reline, how the choice is made

The decision between a local repair and a new liner rests on a handful of findings. We record each one and show you how they point toward one option or the other.

Where the findings are mixed, we say so and give you both options in writing.

• How many sections are damaged, and where
• Whether the tiles are still in line and supported
• Whether damage is visible end to end or only in part
• What the flue serves now and will serve later
• Whether a listed repair system fits the flue's condition

Factory-built chimneys are a different system

Factory-built fireplaces use metal chimney sections rather than a masonry flue. The Florida residential code, in Section R1005.1, says factory-built chimneys shall be listed and labeled and installed and terminated according to the maker's instructions.

Repairs to those chimneys use parts from the same listed system. We identify the system from its labels where they can be read and explain what can and cannot be repaired within its listing. Mixing parts from different makers, or using generic pipe in a listed system, can put it outside its listing. When the right parts are no longer available, replacing the chimney system may be the only compliant choice, and we explain that plainly.