1. Architectural design often proceeds from massing models, solid all the way through, to hollow models with interiors, which we call spatial models. DesignWorkshop facilitates the development of your project from massing to space-defining with the Wallify command. Before you wallify, however, you should establish a block underneath the walls of the building for substructure and to be the ground floor of the building. (Note that the ground floor of most buildings is not literally right at grade. Even at this basic levels, most environment modelers begin to oversimplify when they assume the ground and the ground floor are identical!)
Here's what your model should look like when you've completed the first five parts of this tutorial.
2. To define the substructure block, first click on the main massing block of the cottage to select it.
Then click on the Trim tool in the tool palette, and move the crosshair over the selected block. Notice that the crosshair has a different character when you're in the trim tool. We call this kind of crosshair the "faces crosshair", and it's used by several DesignWorkshop tools. (There is a lot of internal complexity to DesignWorkshop to allow it to automatically provide various different crosshairs according to your working context).
The Trim tool uses the faces crosshair because trims are defined by a trim line you draw on the surface of an object or group. Cut the massing block 2' above the ground, level with the porch floor, by first positioning the crosshair at a point 2' up from the ground edge of the building side, and somewhat in from the side edge. Then press down the mouse button to pin the trim line at that point, and drag sideways first, then up and down carefully to get the trim line exactly horizontal. (If it's close enough, the snap grid will make it exact.) When you release the mouse button, the cut will be extended all the way through the massing block, perpendicular to the face on which you drew the trim line.
3. Click on the Selection Arrow tool, then click on the lower block to select it. Its handles should appear.
If another block is selected instead, click again until you have the walls selected as shown above. Then give the Edit menu Wallify command. When the wall thickness dialog box appears, just click OK (or hit Return) to accept the default half-foot thickness. Your massing block becomes four walls, mitered together at the corners. Even though you can't see inside yet, if you look closely, you can see the change in the projection lines, which are now doubled all the way around.