Creating 3D Geometry - AutoCAD 2011 and AutoCAD LT 2011: No Experience Required - page 852

FiGuRE 16.25 Each of the interior and exterior openings created for the cabin
Creating the Floor, Foundation,
and thresholds
In designing the cabin, you didn't draw a floor but one was implied. The three
exterior doorway openings have thresholds that indicate a small change in level
from the cabin floor down to the decks. You'll now create additional objects to
make the floor, foundation and supports, and the thresholds. Follow these steps:
1. Continuing from the previous set of steps, open the Layer Properties
Manager and do the following:
a. Create new layers called A-DOOR-THRE-3DOB, A-FLOR-3DOB,
and A-FNDN-3DOB; make A-DOOR-THRE-3DOB current; and
give each layer a unique color.
b. Freeze the A-WALL-EXTR-3DOB and A-WALL-INTR-3DOB layers.
c. Thaw the A-DECK-STRS layer.
To see where you're going, look ahead to Figure 16.28. You'll use
the EXTRUDE command to create a series of solids that represent the
thresholds and boxes for the steps and the floor.