This work presents an experiment where a constructive system with hollow blocks is assembled using a robot. These blocks form a stay-in-place support to receive a mixture onsite, generating a monolithic concrete wall with vertical steel reinforcements, as well as providing thermal and acoustic insulation capabilities. The assembly system is tested with an industrial robotic arm, programmed to assemble the blocks following the layout of a building. The tests demonstrate the technical feasibility for execution onsite, with productivity advantages and suitable finishes. Thermal and acoustic performance tests have also been carried out to determine the fillings and structural studies for the complete building layout, along with digital modelling of the design and construction management. The assembly tests have shown the speed and versatility of the robotic system, although the planning and installation of the equipment considering the building as a whole must be developed further.