Gambrel: A roof having two slopes on each side, the lower slope usually steeper that the upper one. Generally seen on farm structures.
Girder Truss: A truss designed to carry heavy loads from the structural members framing into it. Usually a multiple ply truss.
GSL Ground Snow Load: Historical snow load data based on geographical area. Used to design carrying capacities or roof systems.
Header: A girder (wood, composite or steel) located between stud, joist, rafter, or truss openings.
Heel: The point on the truss where the top and bottom chords intersect.
Heel Height: Height of the truss measured from the underside of the bottom chord of the top of the top chord at the end of the truss.
Hip: Intersection of two roof surfaces over an external corner of a building.
Hip Roof: Roof constructed with rafters or trusses pitched over all perimeter walls
Interior Bearing: Term used to describe supports which are interior to two exterior supports.
Joist: A horizontal roof or floor framing member.
King Post: Vertical web at the center of a common or gable truss, or the vertical web at the end of a mono truss.
Lateral Bracing: Members placed and connected at right angles to a chord or web members of a truss.
Live Load: Any loading which is not of a permanent nature (snow, wind, people).
LVL: Laminated Veneer Lumber
MSR: Machine stress rated lumber
Nailer: A member fastened to another member by nails for reinforcement
Nail On Plate: Light gauge cold formed steel truss connector plates with pre-punched holes for manually connecting framing members.
Nominal Span: Horizontal distance between outside edges of supports.
On Edge: Vertical placement of a member’s wide edge
On The Flat: Lumber used in a truss with the wide surface facing up and down.
Outrigger: A wood member nailed to a truss to form overhang beyond the wall line.
Out to Out Span: Same as Overall Span
Over The Wall Height: Height of the truss measured from the underside of the bottom chord to the top of the top chord at the outside edge of an exterior wall.
Overall Height: Vertical distance from the bottom most part of the bottom chord to uppermost point on the top chord.
Overall Length: Same as Overall Span
Overall Span: Outside of frame dimensions (not outside of veneer dimensions).
Overhang: The extension of the top (or occasionally bottom) chord of a truss beyond the heel measured horizontally.
P. Eng: Licensed Professional Engineer
Panel: The chord segment defined by two adjacent joints.
Panel Length: The distance between joints measured along the chord centerline.
Panel Point: The point where a web or webs intersect a chord.
Peak: Point on the truss where the sloped top chords meet.
Piggy Back Truss: A truss made in two pieces usually consisting of a hip type truss with a triangular cap fastened to it. Designed when shipping or manufacturing limitations are affected by overall truss height.
Pitch: Inches of vertical rise for each 12 inches of horizontal run.
Plumb Cut: Top chord end cut to provide for vertical (plumb) installation of fascia
Ply: One truss of a multi truss girder.
Press On Plate: Same as Connector Plate
PSL: Parallel Strand Lumber
Purlin: A horizontal member attached perpendicular to the truss top chord for support of the roofing (ie agricultural steel roofing).