Thresholds generally are used on doorway openings when the level changes
from one side of the opening to the other or to prevent rain and dust from
entering the structure. This usually occurs at entrances that open from or to
the outside. Although they are quite different in shape, each threshold for the
cabin has the same geometry as the steps. The lip of each threshold is offset 2″
(51 mm) from the outside wall, and each edge runs 3″ (76 mm) past the doorjamb
(see Figure 5.3). You’ll use a temporary tracking point with Polar Tracking
and direct entry to draw the three thresholds for the cabin.
As you can see in Figure 5.3, the front threshold is 7′-6″ (2286 mm) wide,
extending 3″ (76 mm) past the doorway on each side. You can draw a line from
the endpoint of one of the jamb lines down 3″ (76 mm) and then draw the
perimeter of the threshold. Here’s how you do it:
1. With AutoCAD running, open your cabin drawing I04A-FPLAYO.dwg
(M04A-FPLAYO.dwg), and use the ZOOM command options to achieve a
view similar to Figure 5.4. The file is also available from this book’s web
page at www.sybex.com/go/autocad2015ner or www.thecadgeek.com.
F igu re 5 . 4 : Zoomed in to the front opening
2. Check to make sure that all buttons except Ortho Mode, Object Snap,
and Dynamic Input on the left side of the status bar are still in their
3. Start the LINE command.
You need to start the threshold 3″ (76 mm) below the bottom
jamb, and in line with the outside wall line. Unfortunately, there is
no feature to snap the cursor to at that point. The techniques that
you’ve previously used would require offsetting the jamb line or
starting the line at the jamb and drawing an overlapping line 3″ (76
mm) downward. Both of these methods would require you to erase
the unnecessary line after the threshold is complete.
Instead of wasting time drawing and then erasing lots of unnecessary
line work, you will begin using the Object Snap Tracking tool.
This tool will help eliminate the need to create unnecessary geometry.
Using the Object Snap Tracking tool requires you to specify a
location in the drawing area, called a temporary tracking point, relative
to existing features or other locations.
4. Click the Object Snap Tracking button on the status bar. In this case,
because the threshold starts 3″ (76 mm) below the outside corner
of the lower jamb, you’ll use that corner as the temporary tracking
point for the start point of the line.
5. Pause the cursor over the outside corner of the lower jamb until the
Endpoint osnap marker appears. A small, green cross displays inside
the Endpoint osnap marker
6. Move the cursor directly downward, and you will see an X appear at
the cursor, directly below the reference point (see Figure 5.5).
F igu re 5 . 5 : Pause the cursor over the endpoint to select the reference point.
The green cross indicates the temporary tracking point for the
Object Snap Tracking tool, and the X indicates the point where the
line will start.
7. Enter 3↵ (76↵) to use the direct entry method to start the first line
3″ (76 mm) below the temporary tracking point. With Ortho mode
turned on, the point selected is directly below the corner of the jamb.
8. Hold the crosshair cursor directly to the right of the last point; when
you see the alignment path and tooltip, enter 2↵ (51↵), as shown in
F igu re 5 . 6 : Using direct input to draw the bottom edge of the threshold
AutoCAD draws the bottom edge of the threshold. You used direct
entry with Ortho mode again, and you didn’t have to enter the relative
polar or the Cartesian coordinates.
9. Hold the crosshair cursor directly above the last point; when you
see the alignment path and tooltip, enter 7′6″↵ (2286↵). AutoCAD
draws the front edge of the threshold.
10. Select Perpendicular from the Object Snap context menu
(Shift+right-click) and move the cursor to the outside wall line.
Alternatively, you can enter PER at the command line to enable the
11. When the Perpendicular icon appears on the wall line, as shown in
Figure 5.7, click to draw the top edge of the threshold.
13. Use the Zoom Extents (ZOOM) command to view the completed front
threshold with the whole floor plan. Remember, by default, doubleclicking
the middle button on a wheel mouse performs a Zoom
Extents (ZOOM) command.
14. Save your drawing as I05-01-FrontThreshold.dwg (M05-01-
FrontThreshold.dwg) by choosing Application menu ➢ Save As ➢