Commercial Structural Framing Systems

The Skeleton of the Building

The structure of life I have described in buildings . . . is deeply and inextricably connected with the human person, and with the innermost nature of human feelings. -Christopher Alexander

Commercial Structural Framing Systems

•Purpose

•Low Rise Framing Systems

•Cast-in-Place Concrete

•Structural Steel

•Load Bearing Walls

•Hybrid Systems

•Cost

•Structural Efficiency

PURPOSE

•The purpose of structural framing is provide

• Strength – Holds the structure up (and holds it down) despite

• Gravity (vertical) loads• Lateral (sideways) loads

• Stability – Maintains the shape and minimizes movement

Commercial Framing Systems

•Low Rise (three stories or less) commercial framing systems may be similar to residential construction

• Wood framing• Light gauge steel framing

Commercial Framing Systems

•Commercial building considerations• Heavy traffic

• Heavier loads

• More wear and tear

• Larger open spaces

• Easy Maintenance

However, usage of commercial buildings often differs from residential usage.

Cast-in-Place Concrete

Wooden forms used to cast slabs

©iStockphoto.com

Cast-in-Place Concrete Frame

Concrete Column

Structural Concrete Slab

Structural Steel

©iStockphoto.com

Structural Steel FramingStructural Steel Column

Open Web Steel Roof Joists

Structural Steel Floor Beams

Steel Decking

Lateral Brace

Courtesy Connie Bertucci

Load Bearing Walls

Masonry load bearing walls with light gauge steel trusses

Courtesy IOP Rec Center

Tilt-up load bearing walls with structural steel and open web steel joist floor and roof framing

Courtesy Tilt-up Concrete Association

Load Bearing Walls

Courtesy Carolina Concrete Masonry Association

Load Bearing CMU Wall

Open Web Wood Floor Joists

Hybrid Framing Systems

Hybrid Systems combine two or more different framing systems

Courtesy TexAZ Business Park

Cast-in-Place Concrete Load Bearing Walls

Structural Steel Framing

Cost

• The cost of construction is an important consideration when choosing a structural system

• The cost of a structure is directly related to the weight of materials used to build the structure

• Lower material weight = Lower cost• Higher material weight = Higher cost

Structural Efficiency

• Ratio of the maximum design load that a structure will carry to the weight of the structure itself• Higher structural efficiency means less material

weight = Lower cost• Lower structural efficiency means more material

weight = Higher cost

Maximum Design Load

Structural EfficiencyWeight of Structure

Design Load = Load a structure is designed to carry

Commercial Structural Framing Systems

•Purpose

•Low Rise Systems

•Cast-in-Place Concrete

•Structural Steel

•Load Bearing Walls

•Hybrid Systems

•Cost

•Structural Efficiency

References

Ching, Francis D. K., and Cassandra Adams. Building Construction Illustrated, 3rd Edition. (2000)

New York: Wiley.

Ramsey, Charles George. Ramsey/Sleeper architectural graphics standards. (2000) New York: John

Wiley.

Image Sources

• Tilt Up Concrete Association. http://www.tilt-up.org/• iStockphoto. http://www.istockphoto.com/index.php• Connie Bertucci, Victor Senior High School, Victor, NY• TexAZ Commercial Properties, LLC• Carolinas Concrete Masonry Association. http://ccmaonline.com/about-carolinas-concrete/about-us.htm