A structural steel system is a parking structure framed with steel columns, beams and girders, with a concrete floor slab, cast-in-place or precast, spanning between the beams.
Steel garages are lighter than concrete garages, erect quickly and can span long distances with relatively shallow members. They are more common in some regions and markets than others, and they are often used where a garage sits over or next to other steel-framed buildings, or where speed and weight drive the decision.
Design considerations
- Corrosion. Exposed steel in a garage sees water, deicing salts and humidity. Galvanizing or high-performance coatings and good drainage are essential.
- Fire. Many open garages can use unprotected steel under the building code, depending on construction type, height and area. Enclosed garages and mixed-use buildings may need fireproofing. See open parking garage.
- Deck. The slab must be protected against cracking and chloride intrusion like any parking deck.
- Vibration. Light, long-span floors need checking for bounce under traffic.
Related systems
- Hybrid steel system: a steel frame with precast double-tee floors.
The Parkonomics view
Steel can be the right garage frame when speed, weight or site conditions favor it. Price the coatings, drainage and future repainting into the comparison, because the life-cycle cost of steel in a salted garage depends on them.
Related terms: Hybrid Steel System, Structural Systems of Parking, Chloride-Ion Contamination, Life Cycle Cost, Steel Bar Joist Systems