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
However, usage of commercial buildings often differs from
residential usage.
•Commercial building considerations
• Heavy traffic
• Heavier loads
• More wear and tear
• Larger open spaces
• Easy Maintenance
Common Commercial
Framing Systems
Cast-inStructural
Place
Steel
Concrete
Framing
Framing
Load
Bearing
Walls
Hybrid
Systems
Cast-in-Place Concrete
Forms are built
Reinforcing is placed
Concrete is poured and finished in place
Wooden forms used to
cast slabs
©iStockphoto.com
Cast-in-Place
Concrete Frame
Concrete Column
Structural Concrete Slab
Structural Steel
Structural members are fabricated off site
Members are delivered to the site
Members are erected per the design
©iStockphoto.com
Structural Steel Framing
Structural
Steel
Column
Lateral Brace
Open Web
Steel Roof
Joists
Steel Decking
Structural Steel
Floor Beams
Courtesy Connie Bertucci
Load Bearing Walls
• Masonry
Courtesy IOP Rec Center
Masonry load bearing walls with
light gauge steel trusses
Load
Bearing • Pre-cast
concrete
Walls • Tilt-up concrete
Courtesy Tilt-up Concrete Association
Floor
and
Roof
Tilt-up load bearing walls with
structural steel and open web steel
joist floor and roof framing
• Wood Framing
• Light Gauge
Steel Framing
• Structural Steel
Load Bearing Walls
Open Web Wood
Floor Joists
Courtesy Carolina Concrete Masonry Association
Load Bearing
CMU Wall
Hybrid Framing Systems
Structural Steel
Framing
Cast-in-Place
Concrete Load
Bearing Walls
Courtesy TexAZ Business Park
Hybrid Systems combine two or more
different framing systems
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 Efficiency 
Weight 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/aboutus.htm