This work considers the technology of implementation of intelligent systems in the area of lifecycle management of building objects at the stage of operation. The main goal of the research is the integration in the process of diagnosis of automated systems for gathering, accumulation, systematization and use of generalized expert knowledge, acquired in the exploration of different objects under different operating conditions. The paper demonstrates the technology of management of the base of rules, with the help of which we built fuzzy knowledge base for the assessment of technical condition of reinforced concrete structures. The rules are formed when comparing the results of inspections to the results of monitoring of the environment. Authors believe that the use of modern universal automated systems of calculation and design, which create information models of buildings and calculate loads on separate structures, provides experts with the possibility to automate forecasting of technical condition of structures under conditions of uncertainty and in cases when a deterministic model of destruction is complicated for practical use or lacking. The results of the conducted research may be used to develop the decision making support systems that are capable by themselves to analyze dynamic information, find regularities in it, perform prediction and explain to the user the logic behind the system's reason of obtaining this or that result.