A
Allowable Strength (ASD)
The maximum load a structural component is permitted to carry in Allowable Strength Design. It equals the nominal strength divided by a safety factor.
Applicable Building Code
The building code adopted by the jurisdiction that governs the design and construction of the structure.
Authority Having Jurisdiction (AHJ)
The organization, agency, or official responsible for enforcing building codes and approving construction.
B
Base Steel Thickness
The thickness of the steel before protective coatings are applied.
Bearing Stiffener
Additional material attached to a member web to prevent web crippling at concentrated loads.
Blocking
A structural element installed between framing members to transfer loads, provide bracing, or stabilize the framing system.
Bracing
Structural elements installed to stabilize framing members and prevent buckling or lateral movement.
Bridging
A system of straps, channels, or braces installed between studs or joists to provide lateral stability and maintain alignment.
C
C-Shape (C-Stud)
A cold-formed steel member with a web, two flanges, and lips. Commonly used as studs and joists.
Chord Member
The top or bottom structural member of a truss.
Clip Angle
A short L-shaped steel connector used to join framing members.
Cold-Formed Steel (CFS)
Steel shapes formed at room temperature from sheet steel through roll forming or press braking.
Collector (Drag Strut)
A structural member that transfers lateral loads from diaphragms to shear walls or other vertical resisting elements.
Component Assembly
A prefabricated structural assembly made primarily from cold-formed steel members.
Component Manufacturer
The entity responsible for producing prefabricated structural components.
Connection
The assembly of connectors and elements used to transfer forces between structural members.
Connector
A device such as screws, bolts, welds, or anchors used to join structural members.
Cripple Stud
A short stud used above or below openings to support sheathing or finishes.
D
Deflection Track (Slip Track)
A track with extended flanges installed at the top of a wall to allow vertical movement of the structure without transferring loads to the studs.
Design Load
Loads determined using code-specified load combinations for structural design.
Design Strength
The strength of a structural component after applying the appropriate resistance factor.
Design Thickness
The steel thickness used in structural calculations.
Designation Thickness
The minimum base steel thickness rounded to a standard mil value.
Diaphragm
A horizontal structural system such as a floor or roof that transfers lateral loads to vertical resisting elements.
Drag Strut
See Collector.
E
Edge Stiffener (Lip)
A small return on the edge of a flange that increases stiffness and strength.
F
Factored Load
The product of a load factor and a specified load in LRFD design.
Flange
The portion of a structural member extending perpendicular from the web.
Floor Joist
A horizontal structural member supporting floor loads.
G
Girt
A horizontal member supporting wall panels and resisting lateral loads such as wind.
Grade
The designation of the minimum yield strength of steel.
Gusset Plate
A steel plate used to connect truss members.
H
Hat Shape
A cold-formed steel section used in truss systems with two vertical webs and a stiffened flange.
Header
A horizontal structural member placed over openings to transfer loads around the opening.
Hold-Down (Tie-Down)
A device used to resist uplift and overturning forces in shear walls.
I
Inspection
The systematic examination of construction to verify compliance with plans and specifications.
Installer
The contractor responsible for installing cold-formed steel framing.
J
Jack Stud
A shortened stud that supports a header over an opening.
Joist
A horizontal framing member used to support floors or ceilings.
K
King Stud
A full-height stud located beside an opening that supports loads transferred by headers.
L
Lateral Force-Resisting System (LFRS)
The system of structural elements designed to resist wind or seismic forces.
Light-Frame Construction
Construction using closely spaced repetitive framing members such as cold-formed steel studs or joists.
Limit States
Conditions beyond which a structural element no longer meets design requirements for strength or serviceability.
Lip (Edge Stiffener)
The stiffening return at the edge of a flange.
Load
Any force acting on a structure including dead, live, wind, seismic, or environmental loads.
Load Effect
The internal forces, stresses, or deformations produced by applied loads.
Load Factor
A multiplier applied to loads in LRFD design to account for uncertainty.
Load Path
The continuous route through which structural loads travel from where they occur, through framing members and connections, down to the foundation and into the ground. Good structures always maintain a clear and uninterrupted load path.
Coincidentally, it’s also the name of a company working to make stronger, tighter, better buildings easier to build.
LRFD (Load and Resistance Factor Design)
A structural design method where factored loads are compared with factored resistance.
M
Mean Roof Height
The average height used to determine wind loads on a building.
Mil
A unit of thickness equal to one-thousandth of an inch (0.001 in).
N
Nominal Load
The magnitude of load specified by the building code before factors are applied.
Nominal Strength
The calculated strength of a member before safety or resistance factors are applied.
Nonstructural Member
A framing member that does not resist primary structural loads.
O
Owner
The individual or entity financing and organizing a construction project.
P
Panel Point
A connection location in a truss where members intersect.
Pitch Break
The point in a truss chord where the slope changes.
Plans (Construction Drawings)
Documents that illustrate the layout and details of a building’s design.
Punchout
A factory-formed hole in a framing member used for routing utilities.
Purlin
A horizontal member supporting roof sheathing or panels.
Q
Quality Assurance (QA)
Inspection and verification performed by an independent professional to confirm compliance with design requirements.
Quality Control (QC)
Procedures implemented by manufacturers or installers to ensure materials and workmanship meet project requirements.
R
Rake Overhang
The horizontal projection of a roof at a gable end.
Registered Design Professional (RDP)
A licensed engineer or architect responsible for design work.
Repetitive Framing
A system where framing members are spaced no greater than 24 inches on center.
Required Strength
The load effect determined by structural analysis.
Resistance Factor (φ)
A factor applied to nominal strength in LRFD design.
Rim Track
A horizontal track installed at the ends of floor joists.
Roof Rafter
A sloped structural member supporting roof loads.
S
Safety Factor (Ω)
A factor applied to nominal strength in ASD design.
Seismic Design Category (SDC)
A classification used to determine seismic design requirements.
Shear Wall
A wall assembly designed to resist lateral loads.
Shop Drawings
Detailed drawings used to fabricate structural components.
Single Span
A structural member supported at only two points.
Slip Track
See Deflection Track.
Span
The clear horizontal distance between supports.
Specifications
Written instructions describing materials, standards, and workmanship.
Steel Sheet Sheathing
Thin steel panels used as structural sheathing.
Strap
Flat steel used for bracing or load transfer.
Strap Bracing
Diagonal steel straps used to resist lateral forces.
Structural Component
A structural member, connector, or assembly that carries load.
Structural Member
A member designed to resist structural loads.
Structural Sheathing
Sheathing capable of distributing loads and stabilizing framing.
Stud
A vertical framing member in a wall system.
T
Track
A U-shaped framing member used at the top or bottom of walls.
Truss
A triangular arrangement of structural members forming a rigid framework.
Truss Design Drawing
Engineering documentation describing the design of an individual truss.
Truss Member
A chord or web element of a truss.
W
Wall Pier
A section of shear wall adjacent to an opening that resists lateral forces.
Web
The vertical portion of a steel member connecting the flanges.
Web Member
A diagonal or vertical member within a truss.
Wind Exposure
A classification used to determine wind load based on surrounding terrain.
Wood Structural Panel
Engineered wood panels such as plywood or OSB used as sheathing.
Y
Yield Strength
The stress level at which steel begins to deform permanently.
Z
Z-Shape
A cold-formed steel member with a Z-shaped cross section commonly used as purlins or truss members.