This book explores the methods and techniques used in the production of polystyrene foam, along with its physical, mechanical, and thermal properties. It presents modern types and approaches to insulating engineering structures, addressing issues related to the durability of insulation systems from the perspective of the thermo-fluctuation strength theory of solids. Additionally, the book proposes a methodology for assessing the longevity of polystyrene foam in various structural applications. Designed for university students specializing in fields such as Industrial and Civil Construction, Urban Development and Management, and Road and Airport Infrastructure, as well as graduate students in areas including Building Maintenance and Reconstruction, Architectural and Construction Materials Science, Resource Conservation and Environmental Impact of Building Materials, and Road Design and Construction.