Steel is an important architectural element in building projects and, when used judiciously, it’s useful, aesthetically pleasing, and cost-effective. This post covers design guidelines for non-structural steel, otherwise known as architectural steel. Structural steel is also an important component of many projects and some of these elements include steel framing, steel stairs and steel moment frames, but this type of steel design is different.
When it comes to architectural steel, it’s important to understand the difference between cold rolled steel and hot rolled. Cold rolled steel is cleaner and straighter which is a huge advantage, but is limited to 12’ lengths and only comes in a handful of cross-sections. Not only do the standard shapes of cold-rolled steel come in handy for components like handrails and guardrails, but just as important, the process of cold rolled steel does not produce mill scale, the flaky surface produced by the hot rolled process. The smooth surface of cold rolled steel requires minimal work to achieve a finished product. While hot rolled steel includes all the heavy lifters of steel profiles, like I-beams, channels, and tubes, they are each subject to mill-scale and require extra effort to achieve a finished product.
Whether the steel is being designed for an interior or exterior condition is also a big driver of the design. Builders typically galvanize the steel at exterior applications and this requires a different set of methods when it comes to fabricating the steel components. A MIG weld that extends fully around the connection at exterior assemblies covers the seam and prevents moisture from working its way between the steel members. While MIG welding isn’t as precise as other types of welds, this matters less as the galvanizing process takes focus off the intricacies of the connection.
At interior applications, TIG welding is preferred as it produces a cleaner, more precise weld with very little excess and less splatter. While TIG welding takes longer, it’s time well spent as interior steel should meet a higher level of precision and refinement.