Mastering Roof Inspections: Asphalt Composition Shingles, Part 20
by Kenton Shepard and Nick Gromicko
The purpose of the series “Mastering Roof Inspections” is to teach home inspectors,
as well as insurance and roofing professionals, how to recognize proper and improper conditions while inspecting steep-slope,
residential roofs. This series covers roof framing, roofing materials, the attic, and the conditions that affect the roofing
materials and components, including wind and hail.
FLASHING, Part 4
Kickout Flashing
Where a wall extends past a roof eave, sidewall flashing stops at the edge of the eave, since this is where
the sidewall condition ends. At the lower roof edge, sidewall flashing should extend out from the wall at least a couple
of inches and be bent to an angle. This is called "kickout" flashing.
Except
for a few manufacturers whose requirements you won’t know about, there are no minimum size requirements.
This particular kickout is bigger than most
you’ll see. Usually, the kickout is cut from a piece of the step-flashing.
This detail is kickout flashing, and its
purpose is to prevent runoff from entering behind the exterior wall-covering where the flashing ends.
Kickout flashing is required regardless
of the type of roof-covering material or exterior wall covering, with the exception of brick and concrete block, since
sidewall flashing doesn’t penetrate the wall with those types of coverings.
Water
cascading down the sidewall joint needs to be diverted to the exterior of the siding when it reaches the edge of the roof.
This kickout needs to have a sealant applied to make the kickout waterproof.
Here are some examples showing kickout
flashing that is missing.
A kickout is easy to fabricate on site.
A piece of step-flashing is cut partially through one flange, and the corner is clipped off.
Then,
it’s bent to shape and installed.
Changes in Roof Slope or Direction
As already mentioned,
the IRC calls for flashing to be installed at areas in which the roof changes slope or direction. Here are examples of some
of these areas.
Valleys
The ways that valleys are flashed often vary according
to the method used for installing shingles in the valley.
Hips
Although hips are similar to valleys in that they’re oriented diagonally to the ridge and create a
change of roof direction, hips don’t get flashing. This is because they tend to shed runoff instead of collecting it
the way valleys do, so there’s much less chance of leakage with hips.
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