Main concrete works of auxiliary reactor building at unit-1 of Rooppur NPP has been completed 8 months ahead of schedule. The building is a part of the Nuclear Island and is designed to house process instrumentation and control devices. The construction time period of the building was reduced by 241 days thanks to logistic processes optimization and workplaces were timely supply with the required resources like materials and tools. The average volume of concrete laid by specialists of NIKIMT-Atomstroy accounted for 1,600 m3 per month instead of scheduled 1,000 cubic meters.Reduced time period in construction allowed reducing the cost, first of all, by means of saving the semi-fixed part of overhead costs and making a significant number of highly qualified labor resources available ahead of schedule, who have already been engaged in performance of other production tasks.Rooppur NPP will be equipped with two Russian VVER-1200 reactors with a total capacity of 2,400 MWe. This is an evolutionary Generation III+ design which fully complies with all the international safety requirements. Engineering Division of Rosatom State Corporation, Russia is the General Designer and General Contractor of the project.