- 1). Examine the window that you want to block to determine if it slides vertically or horizontally. Close the window fully, and lock it before proceeding. Otherwise, your measurements may be off.
- 2). Place a tape measure at the top of the window track, and measure down to the top of the lower sash if your window moves vertically. If the window opens horizontally, measure from the side of the track to the center of the window, where the two sashes overlap.
- 3). Lay a length of 1- or 2-inch-diameter PVC pipe on a work table, and use the tape measure to determine the proper length on it. Mark the length, using a pencil.
- 4). Cut through the pencil line, using a hack saw. Hold the PVC pipe steady with one hand, and saw with the other.
- 5). Go over the cut end of the PVC pipe with medium-grit sandpaper to smooth the rough edges.
- 6). Insert the PVC pipe into the window frame, positioning it either vertically for a vertically sliding window or horizontally for a horizontally sliding window. Position the pipe close to the frame so that doesn't look unsightly. If the pipe does not fit, remove it, and sand the end down more.
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