Kickout flashing, also called a diverter, is a small but critical piece of flashing installed where a roof’s step flashing terminates at a gutter, specifically designed to kick water outward into the gutter rather than allowing it to flow behind the gutter and down the wall or siding below.
Despite its small size, this component addresses a surprisingly common and often serious source of hidden water damage, since without it, water running down a wall-roof intersection has no clear path except behind the gutter and into the wall assembly.
Missing kickout flashing has become a well-recognized issue in the construction and insurance industries, associated with hidden wall rot and even mold growth that can go undetected for years before symptoms become visible.
What Does Kickout Flashing Involve?
- A small, angled piece of flashing at the step flashing termination
- Positioning to direct water outward into the gutter
- Integration with both the step flashing above and gutter below
- Careful installation timing relative to gutter installation
Why Is Kickout Flashing Important?
Missing or improperly installed kickout flashing is one of the more commonly cited causes of hidden water damage in litigation and insurance claims related to construction defects, since the resulting rot often develops slowly behind wall coverings, undetected until symptoms like paint failure or a musty smell finally become noticeable. This underrecognized but consequential detail is worth specifically verifying, whether during new construction, a roof replacement, or a home inspection.
Adding kickout flashing to an existing home lacking it typically requires removing a small section of siding and roofing at the specific junction, a relatively minor and affordable repair considering the potentially significant water damage it prevents.
Kickout Flashing vs. Step Flashing
Step flashing runs continuously along a roof-to-wall junction, one piece per shingle course. Kickout flashing is the specific termination piece at the bottom of that run, directing water into the gutter at the point where the step flashing sequence ends.