Steel vs Concrete
STEEL JOISTS, THE EFFICIENT CHOICE FOR BUILDING CONSTRUCTIONThe best structural system for multi-story residentials, high-rise office buildings and parking garages is steel and steel joists are often the best value on the basis of cost per square foot, scheduling, useable space and design flexibility.
Designers of a 26-story office building and parking garage in Cincinnati saved $2.1 million in foundation and column costs for a 10-level garage because of steel's lighter weight, as compared with an all-concrete structure. A significant consideration in selecting the steel system was the reduction in construction time, 56 weeks versus an estimated 61 weeks for concrete
A steel joist system used in an apartment complex in Buffalo also demonstrates the design flexibility and cost savings of steel joist construction as compared with traditional concrete construction. These buildings combined first-floor commercial space with three floors of housing units, including ground-level parking beneath the living quarters. After investigating alternatives, the designer found a combination of steel frame, steel joists, concrete floors with metal decks, vertical K-bracing and moment-resisting frames to be the most economical. The design saved $300,000.
Steel joists also offer more useable space and broad flexibility. Based on the span of a building, they permit maximum headroom. Pipes and ducts can run easily through joist webs. Steel joist construction is also easy to inspect because it is exposed.
Design flexibility of long spans is possible with steel joists. Spans of over 100 ft are not uncommon. This is also an important factor in remodeling. The greater number of support columns needed in concrete construction often limits the moving of walls and partitions, and they reduce the amount of useable square footage.
Cantilevering with concrete is expensive, demanding form set-up and carpentry to hold the concrete until it cures. Cantilevering with steel joists means only specifying an extended end or a full-depth cantilever direct from the factory.
View projects that have used steel joists in their construction.