All types of outdoor shelters are composed of a steel frame and a canopy of some kind. The type of steel, however, varies with the use of the shelter and, as a result, the two types of steel available are galvanized and powder-coated steel. The former is often used for permanent outdoor shelters like carports and portable garages, while the latter is used for temporary shelters, such as wedding tents and pop-up canopies, that will be up for a day. Both types of surfaces are used to protect the steel from corrosion. While some quick methods of protecting steel include painting the surface, this is only temporary and a more heavy duty covering is more effective for keeping a steel canopy frame intact.
What is the difference between the two, at least on a physical level? For powder-coated steel frames, a dry coating is applied to the steel as a free-flowing, loose dry powder. However, the “powder” used is a thermoplastic or a thermoset polymer. To get the powder to stick to the steel, the dry, loose substance is applied electrostatically. Then, the powder is cured under heat until it solidifies.
Creating galvanized steel, on the other hand, is more of a chemical process to alter the steel compound to prevent it from corrosion. Galvanized steel is created by coating a steel rod or beam with layers of zinc, which directly protects the steel from rust. The steel is submerged in zinc, which, by chemical bonds, permanently becomes part of the metal. The result is, instead of a thoroughly-distributed mix of zinc and steel, a galvanized steel rod or beam with zinc on the outside, a layer below of zinc and iron, and pure steel on the inside. To protect the steel from corrosion, the zinc will corrode first when exposed to moisture or saltwater.