This paper analyzes the main problems of estimating the reliability of buildings and structures. The first of these is the lack of quantitative reduction of bearing capacity of structures and subgrade in the transition of their technical condition from one category to another. The second is the lack of instrumental methods for estimating the bearing capacity. On the base of the great theoretical and practical experience in special facilities the authors propose the monitoring capabilities of the bearing elements of such structures under the static and dynamic loads. Using the integral method of diagnosing the state of dynamically loaded buildings based on the search for diagnostic features to reduce the carrying capacity of structures and foundation soil in the transfer function of the object from a known model of “black box” is suggested. These results open new perspectives for research diagnosis of buildings and structures under dynamic loads. The proposed method has been tested and has been implemented in the cross-sectoral guidance document MRD 01-2011 "Guidelines for screening and monitoring of the technical state of loadbearing elements of buildings and structures", developed at the Mozhaisky Military Space Academy.