Overview

Chimneys and roof-to-wall transitions are the most technically demanding flashing installations in residential roofing — and the most common location for leaks on Florida homes. Improperly installed chimney flashing leads to water intrusion, wood rot, mold, and interior damage. At Trust Roofing, we follow a disciplined process for inspecting, preparing, and installing chimney flashing and roof-to-wall transitions. This training covers the correct approach from inspection through final waterproofing.

Our Field Standards

Chimney and roof-to-wall flashing follows specific Trust Roofing field standards.

Field standards include:
* Existing flashing is inspected and documented — reuse is only permitted when fully serviceable
* Step flashing is installed one piece per shingle course, integrated with the shingle installation
* Counter flashing is properly embedded in the mortar joint or tucked behind siding — not surface-applied
* All exposed flashing edges are sealed with roofing cement or appropriate sealant
* A chimney cricket is installed when the chimney width exceeds 30 inches — required by Florida code
* Completed flashing is photographed before sealant is applied over the top surface

Our Process

Inspection and Assessment

Before touching any existing flashing:
* Inspect for rust, holes, lifted edges, or missing sections
* Check the counter flashing for separation from the chimney or wall
* Photograph all existing conditions
* Determine whether existing flashing can be reused or must be replaced

Installing Step Flashing

Step flashing integrates with each shingle course:
1. Place a step flashing piece against the wall before laying the next shingle
2. The step flashing slides under the next shingle — do not nail through the vertical leg
3. The shingle covers the step flashing horizontal leg
4. Continue one piece per shingle course up the wall

Installing Counter Flashing

Counter flashing overlaps the step flashing:
* For masonry: embed the counter flashing in a mortar joint
* For siding: tuck the counter flashing behind the siding material
* Never surface-apply counter flashing to a wall without embedment — this always fails

Chimney Cricket

When chimney width exceeds 30 inches:
* Build a cricket behind the chimney to divert water around it
* Flash the cricket with step and counter flashing
* Confirm the cricket directs water fully around both sides

Roofing Terms

Step Flashing

Individual L-shaped metal pieces installed one per shingle course along the junction of a sloped roof and a vertical wall, the primary waterproof layer at a roof-to-wall transition and one of the most common leak points when incorrectly installed.

Counter Flashing

The upper flashing layer that overlaps the step flashing and is embedded in a mortar joint or tucked behind siding, diverts water outward from the step flashing. Surface-applied counter flashing without embedment always fails in Florida’s rain conditions.

Cricket

A small peaked structure built behind a chimney wider than 30 inches to divert water around the chimney rather than allowing it to pool, required by Florida building code and one of the most important chimney flashing details in Tampa Bay’s rainfall environment.

Florida Chimney Flashing Inspection

Chimney and wall flashing are among the most commonly failed items on Florida roofing inspections, inspectors verify that counter flashing is properly embedded or tucked, not just surface-applied, and that a cricket is present on chimneys wider than 30 inches.

Mortar Joint

The horizontal joint between courses of brick or masonry where counter flashing is embedded, the correct and code-required method for anchoring counter flashing to a masonry chimney in Florida.

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