Cap flashing is essentially another term for counterflashing, the metal component installed above and overlapping base flashing at a masonry or vertical wall intersection, capping off the flashing system and preventing water from getting behind the base flashing beneath it.
This terminology, emphasizing the flashing’s role capping the system from above, is used somewhat interchangeably with counterflashing across different regions and roofing professionals.
Regardless of which term is used, the underlying function remains the same: providing the top, protective layer of a two-part flashing system at vertical intersections like chimneys and parapet walls.
What Does Cap Flashing Involve?
- Metal flashing overlapping the top of base flashing
- Embedding into masonry or the vertical surface above
- Sealant at the embedded edge
- Coordination with the base flashing system below
Why Is Cap Flashing Important?
Serving the same essential function as counterflashing, cap flashing completes a two-part waterproofing system at vertical intersections, preventing water from working behind the base flashing and compromising the entire assembly’s watertight performance. This capping function is critical regardless of which regional term a particular roofing contractor happens to use for it.
Homeowners comparing quotes or discussing repairs with different contractors should confirm that cap flashing and counterflashing are being used to describe the same component, avoiding any confusion about what specific work is actually being proposed or performed. This shared understanding helps ensure clear communication regardless of the specific terminology used. This clarity avoids any confusion when getting quotes or discussing scope with a contractor. This shared understanding keeps everyone aligned. This holds regardless of local convention.
Cap Flashing vs. Counterflashing
These terms describe the identical component and function, both referring to the flashing that caps off and seals the top edge of a base flashing system at masonry or vertical wall intersections, with terminology varying by region or individual preference.