Cold Formed Steel for Residential Construction – Design Philosophy and Durability Assessment

According to a recent estimate by UN Habitat, approximately 3 billion individuals will require suitable housing by the year 2030. This staggering demand translates to the need for around 96,000 affordable housing units to be constructed each day. However, the conventional construction methods that rely on cement-based concrete and masonry are outdated, lacking innovation, efficiency, and sustainability. In light of these challenges, cold-formed steel emerges as an appealing alternative to traditional construction materials like masonry and concrete. It offers numerous advantages, including easy fabrication, lightweight properties, energy efficiency, the ability to reuse the material at the end of its service life, and a higher level of recyclability. Cold-formed steel buildings are also recognized for their superior insulation and lower energy consumption during operation. Cold-formed steel (CFS) members are created by rolling structurally sound steel sheets into the required shapes using a forming machine, without the need for heat as in the case of hot-rolled steel. While the thickness of these members can range from 0.01 mm to 7 mm, commercial construction of load-bearing walls, roof trusses, and floor joists typically utilizes steel thicknesses of 0.7 mm to 1.2 mm. This paper tries to illustrate the materials and methods employed in the construction of cold-formed steel modular buildings in Sri Lanka[1]. It delves into the material and durability characteristics of cold-formed steel, the design philosophy behind these structures, the development of the building envelope, and the energy efficiency features of the building elements. The findings of this study demonstrate that cold-formed steel buildings can be a highly sought-after alternative for residential construction, offering faster construction timelines, cost-effectiveness, and energy-efficient practices.