Briefcases are also a natural for Z scale layouts. There are a number of fine cases available on the market which are ready to go. If that simply won’t do, you can either fit the layout into an existing case, or you can build a case around the existing layout. If you are building into an existing case, you will need to determine if one of the track radii will fit into the case. Most likely, you will be using the 8510 radius, although you could go to an even smaller radius by using the Märklin flexible track sections (8594), the Micro-Trains flex track or the Peco flex track. However, if you do use such a small radius in this way, the types of equipment that will operate on the layout will be limited. Larger locomotives and cars not only will not operate around the curves, but also will look totally out of place on such a small layout.
For a briefcase, scenery materials are necessarily somewhat limited. Plaster of Paris and paper towel scenery structure does not work well here. Rather, expanded foam or shaped Styrofoam® is more appropriate. The height of the structures and scenery are also limited by the internal depth of the briefcase and the thickness of the framework of the layout, so some exact measurement is required. Otherwise, the scenery technique is much the same, although you must make extra effort to insure that all materials and structures are securely affixed to the layout.