Post Frame Industry Terms

Anchor Bolts: Bolts used to anchor structural members to a foundation. Commonly used in post-frame construction to anchor posts to the concrete foundation.
Bay: The area between adjacent primary frames in a building. In a post-frame building, a bay is the area between adjacent post-frames.
Bearing Height: Vertical distance between a
pre-defined baseline (generally the grade line)
and the bearing point of a component.
Bearing Point: The point at which a component is supported.
Bottom Chord: An inclined or horizontal member that establishes the bottom of a truss.
Cladding: The exterior and interior coverings fastened to the wood framing.
Clear Height: Vertical distance between the finished floor and the lowest part of a truss, rafter, or girder.
Collars: Components that increase the bearing area of portions of the post foundation, and thus increase lateral and vertical resistance.
Components and Cladding: Elements of the building envelope that do not qualify as part of the main wind-force resisting system. In post frame buildings, this generally includes individual purlins and girts, and cladding.
Diaphragm: A structural assembly comprised of structural sheathing (e.g., plywood, metal cladding) that is fastened to wood or metal framing in such a manner the entire assembly is capable of transferring in-plane shear forces..
Eave: The part of a roof that projects over the sidewalls. In the absence of an overhang, the eave is the line along the sidewall formed by the intersection of the wall and roof planes.
Fascia: Flat surface (or covering) located at the outer end of a roof overhang or cantilever end.
Flashing: Sheet metal or plastic components used at major breaks and/or openings in walls and roofs to insure weather tightness in a structure.
Footing: Support base for a post or foundation wall that distributes load over a greater soil area.
Gable: Triangular portion of the end wall of a building directly under the sloping roof and above the eave line.
Gable Roof: Roof with one slope on each side. Each slope is of equal pitch.
Gambrel Roof: Roof with two slopes on each side. The pitch of the lower slope is greater than that of the upper slope.
Girder: A large, generally horizontal, beam. Commonly used in post-frame buildings to support trusses whose bearing points do not coincide with a post.
Girt: A secondary framing member that is attached (generally at a right angle) to posts. Girts laterally support posts and transfer load between wall cladding and posts.
Glued-Laminated Timber: Any member comprising an assembly of laminations of lumber in which the grain of all laminations is approximately parallel longitudinally, in which the laminations are bonded with adhesives.
Grade Line (grade level): The line of intersection between the building exterior and the top of the soil, gravel, and/or pavement in contact with the building exterior. For post-frame building design, the grade line is generally assumed to be no lower than the lower edge of the splashboard.
Header: A structural framing member that supports the ends of structural framing members that have been cut short by a floor, wall, ceiling, or roof opening.
Hip Roof: Roof which rises by inclined planes from all four sides of a building.
Knee Brace: Inclined structural framing member connected on one end to a post/column and on the other end to a truss/rafter.
Laminated Assembly: A structural member comprised of dimension lumber fastened together with mechanical fasteners and/or adhesive.
Loads: 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.
Dead Loads: Gravity loads due to the weight of permanent structural and nonstructural components of the building, such as wood framing, cladding, and fixed service equipment.
Snow Load: A load imposed on a structure due to accumulated snow.
Wind Loads: Loads caused by the wind blowing from any direction.
Lumber Grade: The classification of lumber in regard to strength and utility in accordance with the grading rules of an approved (ALSC accredited) lumber grading agency.
Main Wind-Force Resisting System: An assemblage of structural elements assigned to provide support and stability for the overall structure. Main wind-force resisting systems in post-frame buildings include the individual post frames, diaphragms and shear wall.
Manufactured Component: A component that is assembled in a manufacturing facility. The wood trusses and laminated columns used in post-frame buildings are generally manufactured components.
Mechanically Laminated Assembly: A laminated assembly in which wood laminations have been joined together with nails, bolts and/or other mechanical fasteners.
Metal Cladding: Metal exterior and interior coverings, usually cold-formed aluminum or steel sheet, fastened to the structural framing.
NFBA: National Frame Builders Association. Nominal size: The named size of a member, usually different than actual size (as with lumber).
Orientated Strand Board (OSB): Structural wood panels manufactured from reconstituted, mechanically oriented wood strands bonded with resins under heat and pressure.
Plywood: A built-up panel of laminated wood veneers. The grain orientation of adjacent veneers are typically 90 degrees to each other.
Pole: A round, unsawn, naturally tapered post.
Post: A rectangular member generally uniform in cross section along its length. Post may be sawn or laminated dimension lumber. Commonly used in post-frame construction to transfer loads from main roof beams, trusses or rafters to the foundation.
Post Embedment Depth: Vertical distance between the bottom of a post and the lower edge of the splashboard.
Post Foundation: The embedded portion of a structural post and any footing and/or attached collar.
Post Foundation Depth: Vertical distance between the bottom of a post foundation and the lower edge of the splashboard.
Post-Frame: A structural building frame consisting of a wood roof truss or rafters connected to vertical timber columns or sidewall posts.
Post-Frame Building: A building system whose primary framing system is principally comprised of post-frames.
Post Height: The length of the non-embedded portion of a post.
Pressure Preservative Treated (PPT) Wood: Wood pressure-impregnated with an approved preservative chemical under approved treatment and quality control procedures.
Primary Framing: The main structural framing members in a building. The primary framing members in a post-frame building include the columns, trusses/rafters, and any girders that transfer load between trusses/rafters and columns.
Purlin: A secondary framing member that is attached (generally at a right angle) to rafters/trusses. Purlins laterally support rafters and trusses and transfer load between exterior cladding and rafters/trusses.
Rafter: A sloping roof framing member.
Rake: The part of a roof that projects over the end walls. In the absence of an overhang, the rake is the line along the end wall formed by the intersection of the wall and roof planes.
Ridge: Highest point on the roof of a building which describes a horizontal line running the length of the building.
Roof Overhang: Roof extension beyond the end wall/sidewall of a building.
Roof Slope: The angle that a roof surface makes with the horizontal. Usually expressed in units of vertical rise to 12 units of horizontal run.
Secondary Framing: Structural framing members that are used to (1) transfer load between exterior cladding and primary framing members, and/or (2) laterally brace primary framing members. The secondary framing members in a
post-frame building include the girts, purlins and any structural wood bracing.
Shearwall: A vertical diaphragm in a structural framing system. A shear wall is any end wall, sidewall, or intermediate wall capable of transferring in-plane shear forces.
Soffit: The underside covering of roof overhangs. Soil Pressure: Load per unit area that the foundation of a structure exerts on the soil.
Span: Horizontal distance between two points.
Splashboard: A preservative treated member located at grade that functions as the bottom girt. Also referred to as a skirtboard, splash plank, bottom plank, and grade girt.
Stitch (or Seam) Fasteners: Fasteners used to connect two adjacent pieces of metal cladding, and thereby adding shear continuity between sheets.
Top Chord: An inclined or horizontal member that establishes the top of a truss.
Truss: An engineered structural component, assembled from wood members, metal connector plates and/or other mechanical fasteners, designed to carry its own weight and superimposed design loads.