Family-owned chimney repair serving Bithlo

A coating is not a new crown

BIA guidance on coatings for brick is blunt about what a clear repellent or a brush-on coating can do. Water usually gets into masonry at cracks and separations, and a repellent cannot stop water getting in through ineffective caps or copings or through mortar joints that were never filled.

A coat spread over a broken crown also hides it. The cracks stop showing from the ground while water keeps finding them. The same guidance says a repellent is not recommended in place of common repairs such as repointing or replacing spalled and cracked brick.

When a crown is cracked, broken or has lost its slope, the estimate prices a crown repair or a new crown, not a coating. Any water repellent on the masonry below is a separate question for after the repairs, written as an optional line rather than as the fix for the top.

Flashing metal that lasts

Flashing lives in the wettest spot on the roof. BIA guidance notes that corrosion-resistant sheet metal flashing is required by most building codes, and the Florida Building Code requires metal flashing at wall and roof intersections and around roof openings to be corrosion resistant, with a minimum thickness for each kind of metal.

BIA also says quality flashing materials should be specified because replacement may be expensive and troublesome. Replacing it means cutting out the joints that hold the counterflashing and working the roofing back around the chimney, so a thin or poor metal that fails early can cost far more than it saved.

Our crew uses corrosion-resistant metal at or above the code's minimum thickness. The metal is named on the estimate, so you know what is going into the one part of the chimney nobody wants to open twice.

Cleaning a brick chimney without damaging it

Cleaning brick can do more harm than the dirt it removes. BIA guidance on cleaning brickwork says to select the gentlest effective method and to try it first on a small, out-of-sight area before cleaning the whole surface.

The method is matched to the brick. BIA recommends following the brick maker's cleaning procedure where there is one and trying a bucket and brush or pressurized water before chemical cleaners. Windows, trim and metal nearby are protected, since many cleaning agents, acids in particular, attack metal.

The trial area also shows what to expect, since some cleaning methods change the look of the brick. The estimate names the cleaning method and the test area, and it lists cleaning as a separate line from any repair.

• Abrasive blasting and high-pressure water can etch joints and strip the brick face
• Steel bristle brushes can leave particles that rust
• Improperly mixed or strong acid can etch brick and dissolve mortar

Factory-built chimneys take their own listed parts

A factory-built chimney is a tested system. The Florida Building Code requires it to be listed and labeled, and installed and terminated per the manufacturer's instructions. The listing belongs to the whole system, which in one maker's instructions runs from the pipe and supports through firestops and shields to the chase top and cap.

That is why a generic part is a problem even when it fits. Those instructions, DuraVent's for its DuraChimney II chimney, say to use only its authorized parts, not to mix parts from other systems and not to improvise. A section borrowed from another brand or a cap bent up from sheet metal leaves the chimney outside the conditions it was tested under.

Before any part is quoted, the chimney's maker and model have to be known. On a chimney in Bithlo, our technicians read the label where it can be reached and write the maker and model on the estimate, so each replacement matches the system already in the house. If the system can no longer be matched, that is said plainly.