The construction industry is the largest consumer of material and energy resources. Resource saving makes a great contribution to energy, environmental security and improving the quality of life of the population -the constituent elements of national security. An important part of resource saving is improving the energy efficiency of buildings. The problem of energy efficiency has been relevant for more than fifty years. Energy-efficient buildings must meet the requirements of minimum energy consumption not only at the design stage, but in general throughout the life cycle, which includes the processes of design, construction and installation works, construction control, operation and disposal. Improving of the energy efficiency of buildings is the process of bringing the design of the total reduced costs of external walling and heating of the building to the minimum possible value. The main elements of the operating costs for heating the building are fuel costs. Therefore, the optimization of the level of thermal protection of buildings will not only increase the level of energy efficiency and comfort of civil buildings, but also provide a significant economic effect, the value of which will continuously increase in accordance with the life of the building. The method of optimizing the level of energy efficiency, including thermal protection of buildings for various purposes, should help to improve the balance of wall materials and structures, so that the production of the most costeffective products continuously increases and, accordingly, the share in the balance of less economical products decreases. As a result of this restructuring of the building materials industry can get a significant economic effect. Thus, there is a link between the level of thermal comfort of civil and industrial buildings and the increase in productivity, the reduction in the number of diseases of workers, the reduction of the corresponding costs of production and health care and, ultimately, the growth of national income.