It is customary for the preparation of technical documentation to use CAD (computer aided design) systems. Depending on the design and functionality they are divided into low, medium and high class. In certain cases, there are developed alternative software applications or such added to other basic systems with broad opportunities for development. At the present time open source programs are more widely used. This reinforces the interest of designers, engineers and architects to find possible application of such programs in the workflow. Contemporary and very good solution gives Blender free software with specialized application "MeasureIt".