- 1). Slip the oval window into the building's framed opening. Verify the window's frame slides into the hole and the window's mounting fin, the mounting flange surrounding the window's perimeter, overlaps the opening's framing. Remove the oval window and adjust the framing as needed.
- 2). Apply a continuous 1/4-inch-wide bead of window-grade caulking around the perimeter of the interior side of the oval window's mounting fin. Place the caulking bead between the fin's nail holes and the edge of the window frame.
- 3). Slip the window into the exterior of the building's frame. Tack the top of the window to the framing with a 1-3/4-inch galvanized nail, using a hammer to drive the nail. The single nail at the top of fin allows the window to move slightly side to side.
- 4). Enter the building and check the window's fit in the opening. Adjust the spacing between the window and the framing with shims until the window sits evenly in the opening.
- 5). Drive 1-3/4-inch galvanized nails through each of the fin's nail holes and into the building's framing with the hammer.
- 6). Press flashing tape against the oval window's fin and the building's framing. Apply the tape in two sections. Stick the tape to the bottom half of the oval first, then cover the top half. Flashing tape's sticky side seals the seam between the fin and the framing; the tape's coated side repels moisture.
- 7). Remove the shims from the inside of the window frame, if used. Pack insulation into the space between the perimeter of the window frame and the building's window framing.
- 8). Install the building's exterior siding and interior drywall or other wall covering.
- 9). Fill the seam between the oval window's exterior window frame and the siding with window-grade caulking. Fill the seam between the interior window frame and the wall covering with the appropriate sealer or caulking.
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