How to Install Head Flashing with ZIP System Flashing Tape

September 1, 2020


Finish the window flashing by overlapping the top over the side pieces.

With the sill flashed and the window installed, it is time to finish the job by sealing the top of the window shingle-style.

How to flash the window head:

  • Cut flashing tape to be at least two inches longer than the width of the window plus side jamb flashing.
  • Make sure top of head flashing is at least two inches above where the top of the head flange ends.
  • Make sure head flashing runs at least one inch past the jamb flashing on each side of the window.
  • You can use ZIP System® 3-3/4 inch tape for this application, but to get a better adhesion surface and width to make sure a good shingling pattern is maintained, use 6 inch ZIP System flashing tape.
  • Use J-roller to seal flashing to sheathing. Focus on wrinkles or air pockets, which can become 'fish-mouths', which can allow water to creep in.
  • Seal window from the interior with a low expanding foam.
—This video is provided by ZIP System sheathing and tape, one of ProTradeCraft’s advertisers. A next-generation exterior roof and wall solution, ZIP System streamlines the weatherization process with an integrated water-resistive barrier and taped seams replacing the need for house wrap or felt, while eliminating the risk of trapped water between sheathing and barrier and protecting against air leakage. View all ZIP System's content