Download the file called SmallBuilding01.zip (2 MB) and unzip them to your hard disk.  Then double-click the HTML file to play the video in your browser.  

This series of tutorials are intended to show a workflow that I use for most of my architectural projects that are based on working with 2D elevations extruded to create wall thicknesses.  The main purpose is to avoid the use of 3D Boolean operations to cut window and door openings.  3D Boolean operations use significant computer resources and often creates long thin triangles resulting in problems with lighting and materials.

Good luck and have fun
Ted