Numerical control, 3D technique and new materials have great potential in the automation of construction processes, simultaneously with the release of man from hard physical work and allow to improve the quality of workmanship and minimize waste. In construction, vertical elements are erected automatically, and flat coverings are made of prefabricated elements. In the "Stroptronic" technology presented, the automatic robot arranges all materials in one cycle and forms a monolithic, reinforced ceiling slab temporarily supported on the board sliding and on supporting rollers during the maschine passage. Concrete on a quick-setting cement based on based on calcium sulfoaluminate (CSA) thanks to its high early strength (over 20 MPa, 1.5 hours after making it with water) ensures the ceiling self-bearing capacity in a short time. The robot constantly introduces reinforcement, prepares and extrudes the concrete mix, moving in a direction perpendicular to the ceiling span. Along with the robot, the slide board and support rollers move slowly under the ceiling, providing continuous support for the binding concrete over a distance of about 1m, i.e. until the plate reaches self-bearing capacity, in the cross-section between the supports. In the example of the ceiling fragment with composite inserts (main bars - steel, distribution bars - made of fiberglass) and the results of preliminary tests of the concrete on CSA cement as well as the conditions for the progress of works during the laying materials and conclusions were presented.