There are many advantages, over conventional building materials, when building with ISBU Corten steel containers. 1. Their sturdy steel structure allows for design options not available with many other materials, such as wood. The strength of steel provides stacking, cantilevering and other choices not available when using other materials. 2. With proper safeguards, these steel units can be buried beneath the surface, thus utilizing the soil for additional insulation, protection and concealment. 3.