One of the perspective and modern methods of nondestructive testing – thermal control is considered. The possibilities and advantages of thermal control in the identification of defects in various building materials and products, enclosing structures of buildings and structures are given. The short characteristics of the main defects of building materials and products, buildings and structures are proposed. The basic principles of identification of hidden (invisible) and obvious (visible) defects are briefly considered and practical results of construction flaw detection of objects for various purposes with the use of thermal imaging equipment are presented. On the example of a fragment of the enclosing building structure of piece building products in the form of ceramic bricks with artificially created technical defects in the process of qualitative analysis of thermograms zone of thermal temperature anomalies (method of active thermal control) are localized. For some enclosing structures of buildings and structures based on the results of thermal imaging identified obvious thermal defects, their qualitative analysis and recommendations for elimination (method of passive thermal control) are made.