Steel Frame Construction
A skeleton of steel columns and beams that carries a building's loads.
Quick Answer
Steel frame construction is a structural method that uses a skeleton of steel columns, beams, and bracing to carry a building's gravity and lateral loads, with floors, roofs, and cladding attached to it. Members are fabricated off site, shipped, and bolted or welded together on site.
The Full Picture
In a steel frame building, the structure is a connected framework of vertical columns and horizontal beams, often with diagonal braces or rigid connections to resist wind and seismic forces. Floor decks, roof decks, and non-load-bearing walls are then supported by the frame. Because loads travel through the skeleton, walls can be lighter and openings larger than in load-bearing masonry.
Steel members are typically fabricated in a shop from detailed shop drawings, then shipped to the site for erection. Connections are bolted or welded, and fireproofing is applied to protect steel from heat. Design and fabrication standards come from the American Institute of Steel Construction (AISC), and OSHA regulates safety requirements for steel erection in the United States.
The method is widely used for commercial buildings, hospitals, industrial facilities, warehouses, stadiums, and tall buildings. Steel offers high strength relative to weight, long spans, and fast erection, but it requires fire protection, corrosion protection in some environments, and lead time for fabrication, particularly for specialty members.
For contractors, the schedule hinges on early procurement of steel and coordinated shop drawings. Detailers, fabricators, erectors, and other trades such as decking, fireproofing, and mechanical contractors need aligned information, since connections, penetrations, and tolerances touch many scopes. Changes after fabrication begins can be expensive.
Real Examples
Common Misconceptions
People assume: Steel frame buildings do not need fire protection because steel does not burn.
Actually: Steel loses strength at high temperatures, so structural steel typically needs fireproofing or other protection depending on the code and construction type.
People assume: Steel framing is the same as light-gauge metal stud framing.
Actually: Structural steel uses heavy rolled or built-up shapes for primary structure. Light-gauge steel studs are a separate, lighter system generally used for walls and smaller buildings.
Frequently Asked Questions
What is steel frame construction?
A building method in which steel columns, beams, and bracing form the primary structure, with floors, roof, and cladding supported by that frame.
What buildings use steel frames?
Commercial offices, hospitals, industrial and warehouse buildings, stadiums, and high-rises commonly use steel, along with many mixed-use and institutional projects.
What are the advantages of steel framing?
High strength-to-weight ratio, long spans, off-site fabrication, and quick erection. Tradeoffs include fireproofing, corrosion protection, and fabrication lead times.
How is steel frame different from reinforced concrete?
Steel frames use fabricated steel members connected on site, while reinforced concrete is formed and poured, or precast. Each has different cost, schedule, fire, and span characteristics.
What standards apply to structural steel?
AISC publishes the specifications for structural steel buildings, the building code adopts them, and OSHA's steel erection standard covers worker safety.