How to Trim Windows for a Ranch Casing
- 1). Hold your level along the top span of the window. Put it 1/4 inch above the edge. Make a pencil mark all along it, extending the mark 1/4 inch out over both ends of the opening.
- 2). Measure the length of the line and transfer the measurement to a piece of casing trim. Put your two marks at the very bottom (thinner) edge of the trim. Set the trim on a miter saw, with the bottom edge of it facing the blade. Put one of the two marks under the blade.
- 3). Turn the blade to 45 degrees, pointing away from the main span of the trim. Make the cut. Slide the trim so the other end is under the blade. Turn the blade to 45 degrees in the other direction (so it again points away from the main span). Make the cut.
- 4). Set the board in place at the top of the window, with the bottom (shorter) side of the trim sitting on the line that you drew. The bottom should come out over the ends of the window by 1/4 inch on either side, then angle up and out further to the tops. Secure the piece with the trim nailer, shooting in pairs of nails every foot.
- 5). Measure and miter the trim for the other sides of the window, using the same procedure. Use your trim nailer to secure them, with the miters forming the corners.
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