How to Install Step Flashing

What You'll Need
Platforms or staging for edge or eaves work
Measuring Tape
Utility Knife
Tin Snips or Shears
Hammer-Tacker and staples
Tool belt
Roof hammer or pneumatic nailer

Flashing installation is not as complicated as it sounds. The right tools and guide should be able to help anyone install step flashing. Being able to install step flashing can save a great deal of money. Most contractors tend to charge great sums for their labor so it’s better to personally install the step flashing. Aside from saving money, it can also be a very educational experience. Prior to step flashing installation, safety precautions should be noted. The following guidelines will help anyone ensure that their step flashing installation is safe:

  • Step flashing installation should only be done if the weather is good. The kind of weather can affect the person working on the installation. Forcing to do the installation when the weather is not good can only lead to health problems. Experts advise that installation should be down when the temperature is around 30 to 80 degrees.
  • It’s best to work with someone. Working alone may lead to accidents and other problems. The job is also easily done when two or more people work together.
  • Before working on the step flashing, all power line or cable lines should be noted.

There are several steps to follow in order to successfully install step flashing.

Step Flashing Installation

Instead of purchasing all these materials, there are local hardware stores offering rental tools instead. Some of these materials are seldom used so it’s better to rent them for step flashing than to buy them.

Roof Preparation

Before installing the step flashing, the roof needs a felt underlayment. Typically, roofing felt underlayment should weigh around 15lb.  To do this, staple the felt layers from the edges outside. At least 3 inches of felt rolls should over lap one another. The felt rolls should be stapled securely. It is important that the layers stay intact and tear-free. In order to properly secure the rolls, a lot of staples can be used. After stapling the layers of felt, the metal trim is attached to the edges. A “drip-edge” is used all throughout this step. Rake-edges can also be used for the sides of the roof. All the layers are properly secured using roofing nails.


Depending on the product and the manufacturer, there are different ways to install the step flashing. Most product packages come with their own set of instructions so installation is not hard. Follow the instructions and the images indicated in the package. Cut off tabs are usually used for the starter row of the step flashing. Full shingles are layered from the roof’s outside corner. In order to start the installation, shingles should be layered accordingly. For each row of shingles, it will go back half-tab. Some shingles need to be cut off before they can be installed. The last step of the process is to install the kickout flashing. It is important to ensure the flashing goes beyond the drip edge by around 1 1/2”. To check if the installation is properly done refer back to the instructions.