Gutter Apron

A gutter apron (sometimes called kick-out flashing or step flashing at the eave) is an L-shaped metal strip — typically galvanized steel or aluminum — that slides under the bottom course of roof shingles and bends down over the back lip of the gutter. Its purpose is to bridge the gap between the roof deck and the gutter's back edge, ensuring that water running off the shingles always falls into the gutter rather than behind it and down the fascia.

Without a gutter apron, water from wind-driven rain, ice dams, or heavy flow from steep pitches can travel behind the gutter by capillary action or direct splash. Over one to three seasons, this soaks the fascia and sub-fascia, initiating the rot cycle. The gutter apron is a simple, inexpensive component — typically sheet metal cut on-site or purchased as pre-bent lengths — but it is frequently omitted on older installations or DIY jobs.

When replacing gutters, a good contractor installs new gutter apron flashing as a standard part of the job. On existing gutters where fascia rot has been found, installing an apron is often the first corrective step, followed by fascia repair or replacement.