The definitions of volumes and voids are similar in CADAM3D. To define a volume or void, in the 3D space, a cross-section of the element must be defined in one of the Cartesian planes (XY, XZ or YZ) together with the plane of extrusion. The latter is determined using 3 extrusion heights.

The Add a volume command generates the Volume Editor window.  The volume name is optional but recommended if you have multiple volumes and voids.