What Is Gutter Flashing?

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  • 1-8 hours
  • Intermediate
  • 30-50

Gutter flashing is a versatile waterproofing tool that can be used to keep water away from one area by diverting it to another. Flashing can be bought by the foot and is recommended as a way to increase the efficiency of your gutters.

Gutter Flashings

Gutter flashing can be installed just beneath the roofline and inside the gutter. They work by stopping water from running behind a gutter and seeping into building materials and the infrastructure of a house. Flashings are bent at a 35-degree angle, which is statistically the best for diverting water.


Gutter flashing comes in a standard size of 2x3 inches, 10 feet long. However, depending on the material required, you can have gutter flashings made to fit if water leakage around your roof is a big problem. Standard pieces will be cut to this size, but you can order large lengths of flashing that you can cut to size yourself.


Gutter flashing comes in 2 different types of materials which are aluminum, and plastic. Plastic is used for its ability to adapt to complex gutter systems, while aluminum is used for its durability and the fact that it will last a lot longer despite being more expensive.