How to Attach Solid Vinyl Window Casing
- 1). Measure from the top of the window down to 1/4 inch from the bottom. Mark it with a pencil and repeat the process for the opposite side of the window. Verify that the window is level by setting a level between the two marks. If they are not level, adjust one mark down or up until they are perfectly even. Write down the measurement from the top of the window to the mark made near the bottom.
- 2). Measure two pieces of casing to match that measurement for the height of the trim. Cut both pieces of casing to this measurement using a miter saw. Set the saw to a 45-degree angle to make the cut.
- 3). Line the first piece of casing up along the height of the window and nail two trim nails in, one at both the top and bottom. Line the second piece up on the other side and install it in exactly the same manner as the first piece.
- 4). Measure the width of the window between the casing pieces at the top of the window and write down the measurement. Cut one piece for the top at 45 degrees. Lay the piece between the two vertical pieces and nail it in at each end.
- 5). Measure the length of the stoop on the bottom of the window and subtract 1 inch to get the measurement of the final bottom piece of casing. Write down the measurement and cut the final piece of casing to the desired measurement at an angle of 10 degrees. Cut the 10-degree angle on both sides of the casing. Set the piece against the wall under the sill and make sure it is centered before nailing it to the wall.
- 6). Install nails on each of the pieces of casing so it is firmly attached to the wall. Put additional nails around the edges of the casing and near the ends. Caulk over any nails that may be visible and any gaps in the vinyl casing.
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