Truss Terminology G-L


Portion of the end wall above the eave line of a double sloped roof.

Gable End Frame

A component manufactured to complete the end wall of a building. The bottom chord of the gable end frame is continuously supported by the end bearing wall. Verticals between the top and bottom chords are typically spaced at 24" on center. The verticals function as load carrying members and as attachment members for sheathing or other end wall coverings. The gable end frame must be incorporated into the end shear wall by the building designer.


Roof having two slopes on each side of the peak, the lower slope usually steeper than the upper one.

Girder Truss

Truss designed to carry heavy loads from other structural members framing into it. Usually a multiple-ply truss.


Designation of the quality of a manufactured piece of wood.

Ground Bracing

Used to provide stability for the first Truss or group of Trusses installed. It is composed of vertical and diagonal members providing support for the installed Trusses from the earth, floor, foundation or slab. Ground Bracing should be located in line with the Top Chord Lateral Restraint. Proper Ground Bracing also requires lateral and strut Bracing to ensure stability and support.

Gypsum Board

Interior finish sheet material manufactured with gypsum.


Structural member located between stud, joist, rafter, or truss openings.

Heel Joint

Point on the truss where the top and bottom chords intersect.

HIB-91-Commentary and Recommendations for Handling, Installing and Bracing Metal Plate Connected Wood Trusses

Publication of the Truss Plate Institute (TPI) providing recommendations and guidelines to contractors for handling, installing and bracing metal plate connected wood trusses for applications up to 2' on center. This publication has been replaced by the Building Component Safety Information (BCSI) booklet.

Hip Corner

Either truss or conventional framing, that along with the end jacks, forms the hip ridge and roof areas between the end wall and hip girder.

Hip Girder

Truss designed to carry end jacks and hip corners or common framing.

Hip Roof

Roof system in which the slope of the roof at the end walls of the building is perpendicular to the slope of the roof along the sides of the building

Hip Set

Series of step down trusses of the same span and overhang, that decrease in height to form the end slope of a hip roof system.

Hip Truss

Trusses used in a hip set roof system. Each Hip Truss has the same span and Overhang as the adjacent standard Trusses but decreases in height with the top and bottom chords of its center portion parallel to each other and horizontal. Also referred to as a step-down Truss.

Horizontal Shear

Shear that occurs in planes parallel to the longitudinal axis of the member; sometimes referred to as longitudinal shear.

Hydraulic Press

Press consisting of a "C" clamp hydraulic cylinder; or an I-beam platen, or flat upper pressing platen, powered by hydraulic cylinders that are used to embed metal connector plates into a truss.


Structural member manufactured using sawn or structural composite lumber flanges and structural panel webs, banded together with exterior exposure adhesives, forming the cross-section shape of the capital letter "I". These members are primarily used as joists in floor and roof construction.

Impact Load

Load resulting from moving machinery, elevators, craneways, vehicles or other similar forces and kinetic loads.

Installation Lateral Restraint

Lateral Restraint that is attached to Truss members during installation of the Trusses and is intended to be temporary. See Lateral Restraint.

Installation Restraint/Bracing

Lateral Restraint and Diagonal Bracing installed during construction for the purpose of holding Trusses in their proper location, plumb and in plane, until Permanent Individual Truss Member Restraint, Diagonal Bracing and Permanent Building Stability Bracing are completed.

Interior Bearing

Supports that are interior to two exterior supports.


Fixture that holds the truss in position until rigidly fastened with connectors.


Horizontal roof or floor framing member.


Web at panel point above a cantilever bearing.

Knee Brace

Brace positioned between a column and truss panel points when trusses are supported by columns lacking transverse bracing.


Portion of a branch or limb that has been surrounded by subsequent growth of the wood of the tree. As a knot appears on the cut surface it is merely a section of the entire knot, its shape depending upon the direction of the cut.

Ladder Panel

(Ladder Framing) Prefabricated panel fastened to the roof eave to create a sloped overhang.

Laminated Veneer Lumber (LVL)

Composite of wood veneer sheet elements joined with an adhesive with wood fibers primarily oriented along the length of the member. Veneer thickness does not exceed 0.25".

Lateral Bending

Bending out of the plane of the Truss.

Lateral Restraint

Also known as continuous lateral brace or CLB. A structural member installed at right angles to a chord or web member of a Truss to reduce the laterally unsupported length of the Truss member (See BCSI-B1, BCSI-B2, BCSI-B3, BCSI-B7, and BCSI-B10).

Legal Requirements

Applicable provisions of all statutes, laws, rules, regulations, ordinances, codes, or orders of any governmental authority of the United States of America, any state, and any political subdivision or quasi-governmental authority of any of the same, including, but not limited to, departments, commissions, boards, bureaus, agencies, counties, municipalities, provinces, and other instrumentalities.

Let Tails Run

When a piece of lumber making up the top chord is not cut off to a specified overhang length, but retains the length of the lumber used for the purpose of meeting specific overhang requirements in the field.

Level Return

Lumber filler placed horizontally from the end of an overhang to the outside wall to form a soffit.

Live Load

Loads produced by the occupancy of the building or structure, not including construction loads or environmental loads such as wind loads, snow loads, rain loads, earthquake loads, flood loads or dead loads. Live loads on a roof are those produced during maintenance by workers, equipment and materials, and during the life of a structure by people and moveable objects.


Forces or other actions that arise on structural systems from the weight of all permanent construction, occupants and their possessions, environmental effects, differential settlement and restrained dimensional changes.

Load-Bearing Wall

Wall specifically designed to transfer loads from above to the framing or foundation below.

Local Building Official

The individual or organization who in accordance with the Legal Requirements may impose requirements on Truss Manufacturers and Truss Designers relating to the Trusses and the Truss Submittals.

Long Span Trusses

Trusses over 60' in length.


Direction parallel to the grain of wood.


Product of the sawmill and planing mill usually not further manufactured other than by sawing, resawing, passing lengthwise through a standard planing machine, crosscutting to length, and matching.