How to Replace the Flashing on Replacement Windows
- 1). Use your pry bar to remove your window unit from the buck, or window opening, area. Use a metal putty knife to remove all of the old flashing from the buck area.
- 2). Cut your first strip of flashing a bit longer lengthwise than the bottom of your window's framing using your scissors or utility knife. Make the strip is wide enough to fit over the sill and window jamb areas.
- 3). Cover the window jamb, sill and horn at the bottom of the framing area by sticking the flashing over it. Use spray foam insulation to account for any air gaps that you might have missed.
- 4). Cut the window flashing membrane for the two sides a little bit longer than the sides of the window and stick the flashing to the sides. The added length will help you avoid air gaps and pockets that may occur at the edges if you cut the exact length of the window sides.
- 5). Cut the window flashing membrane slightly larger than the top of the window area. Peel off the back and stick it into place, slightly overlapping the side membrane pieces.
- 6). Repeat these previous steps on the exterior side of the window and install the window over the newly installed window flashing membrane.
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