There are increasing demands for improvements in standards of construction quality, comfort and performance in building internationally. The building industries in many countries are looking for new and improved methods for construction. Light steel structure provide alternatives to traditional forms of construction, but the future growth of steel structure will depend on the ability of the industry to provide high quality, economical steel structure systems which meet the needs of the builder and the home owner. Any evaluation of a construction method must look not only at the structural requirements but also at the total performance of the building. Structural requirements for buildings using cold formed steel sections are covered by various standards and design manuals. Load bearing tables and all information that designers and building officials need are generally available from steel manufacturers. Increasingly, energy efficiency issues have come much more important in the assessment of a construction system. In particular, the ability to provide the required thermal performance so that excessive heating or cooling are avoided, and comfort is maintained. Furthermore, concerns over global warming have led to an international commitment to reduce emissions of global warming gases. The objective of this work is to increase the understanding of how light steel structure (tube) construction should be designed to ensure that buildings using this technology can achieve excellent comfort conditions and be used in an energy efficient manner with special reference is given to cold formed steel stubs filled with slag stone concrete. This concept is totally in concordance with the sustainable development as the aim is to design light steel structure buildings which are comfortable to live in, achieve energy efficiency requirements, and result in low greenhouse gas emissions, in addition the recovery of industrial waste (slag). Thermal properties of concrete slag stone concrete samples are measured, and then thermal behavior of the composite elements was estimated using thermal network methods which allow the calculation of thermal resistance of wall with light steel structure in order to evaluate the effect of the slag stone in the thermal performance of light steel building using the cold formed steel stubs filled with slag stone concrete.