Square tubing buildings are the lightest-duty and most economical of all steel-framed structures. Typically used in carports, small shop buildings, and add-ons like lean-tos, square tubing provides a good alternative to engineer stamped solutions offer by Metal Roofing Supply. We will design a square tubing structure ONLY when no engineer approval is required. We typically use 2 ½” 14 GA galvanized materials with 2 ¼” connectors. Metal Roofing Supply offers carports in 12’, 18’, and 24’ wide standard sizes, which can be fabricated in 10 working days. A custom tubing building is best designed when it does not exceed 30’ in width, 50-60’ in length, and 14’ in height. Tubing buildings are simple to erect but come with no plans, calcs, and reactions, or engineer stamps.