Definition Of Technical Terms

Accessory: A supplementary building product, such as door, window, skylight, ventilator, louver, etc.

Anchor Bolts: Bolts used to anchor structural members to a concrete floor, foundation or other support. Usually refers to the bolts at the bottom of all columns and door jambs.

Anchor Bolt Plan: A plan view of a building(s) foundations showing all imensions and sections required to properly locate the anchor bolts, including the projections of the bolts above the concrete surface, required recess, etc. Column reactions (magnitude and direction), and base plate dimensions are also included.

Approval Drawings: Drawings sent to the customer to verify design and dimensions and to verify the sales contract description of materials and services the manufacturer has agreed to furnish.

Auxiliary Loads: All specified dynamic live loads, other than the basic design loads, which the building must safely withstand. Examples are loads imposed by crane systems, material handling systems and impact loads.

Base Angle: A continuous angle fixed to the floor slab or to the grade beam to enable the attachment of wall panels.

Base Plate: The endplate of a column, which rests on the supporting substructure surface.

Bay: The space between the center lines of frames or primary supporting members in the longitudinal direction of the Building. Also called Bay Spacing or Bay Length.

Bead Mastic: A sealant furnished in a continuous roll, normally used for sealing end laps of roof panels. See also Endlap Mastic.

Blind Rivet: A small headed pin with an expandable shank for joining light gauge metal. Typically used to attach flashing, gutters, etc. Also referred to as a Pop Rivet.

Brace Grip: Galvanized steel strands formed into a helical hairpin shape that is wrapped tightly on the strand at the end of the cable brace.

Brace Rods/Cables: Rods or cables placed diagonally in the roof and walls for the purpose of transferring wind loads to the foundations and longitudinally stabilizing the building.

Braced Bay: The bay where bracing is provided.

Bracket: A structural support projecting from a column or rafter to which another structural member is fastened. Example: Brackets supporting crane runway beams.

Building Width: The lateral width of the building measured from out to out of sidewall steel lines.

Built-up Section: A structural member, usually an “I” shape, made from individual flat plates welded together.

Butt Plate: The end plate of a structural member which usually rests against a similar end plate of another member to form a moment resisting connection. Also called Splice Plate, End Plate, or Cap Plate.

“C” Section: A member formed into a “C” shaped profile by cold roll-forming from coils.

Cable Catch Assembly: The operating handle used to open and close the ridge ventilator.
Cantilever: A projecting beam that is supported and restrained at one end only.

Canopy: An overhanging or projecting roof structure, below the eave level, supported at one end only.

Catwalk: A narrow walkway used to provide access to Mechanical equipment normally supported on roof platforms.

Checkered Plate: Flat hot rolled plate with raised checkered design to prevent slipping; used for industrial equipment platforms, catwalks, stair treads, etc.

Clear Height: The vertical dimension from the finished floor level to the lowest underside point of the rafter.

Clear Span: A building without internal columns.

Clip: A plate or angle used to fasten two or more members together.

Cold-Formed Member: A light gauge structural member produced from coiled steel stock running through a series of rolls at normal room temperatures.

Collateral Load: is the weight of additional materials permanently fixed to the building (other than the dead load and the live load of the building) such as fire sprinklers, mechanical systems, electrical systems, false ceilings, partitions, air conditioning etc.

Column: A vertical structural member used in a building to transfer loads from the main roof beams, trusses or rafters to the foundation.

Concrete Notch: A rebate or notch formed along the edge of the concrete floor slab or grade beam, allowing wall panels to end below the floor level thus preventing ingress of dust or water.

Counter Flashing: Trim used to connect the sidewall sheeting of a main building to the roof sheeting of a lower building.

Crane Beam: A beam that supports an overhead traveling bridge crane. On under hung bridge cranes, it also acts as a crane rail. Also known as a Crane Runway Beam.

Crane Rail: Rail welded or bolted to a crane beam forming the track on which the bridge crane wheels travel.

Curved Eave: Curved panels provided at the eave.
Damper: Baffle plate in a ridge ventilator that can be opened or closed using the cable catch assembly.

Dead Load: The self-weight of the pre-engineered building structure including all its components such as frames, floors, secondary members, sheeting, bolts, etc.

Design Codes: Regulations developed by recognized agencies establishing design loads, procedures, and construction details for structures. Examples are: MBMA, AISC, AISI, AWS, etc.

Double Channel: Double or back-to-back “C” sections stitch bolted together.

Double Sliding Door: Sliding door with two door leaves.

Downspout: Cold-formed sheet metal section used to carry water from the gutter of a building to the ground or storm drainage system.

Downspout Elbow/Shoe: Cold-formed sheet metal section, matching the downspout profile, attached to the lower end of a downspout and curved in such a way as to direct water away from a wall.

Eave: A line along the sidewall formed by the intersection of the inside faces or planes of the roof and the sidewall panels.

Eave Gutter: Gutter at the eave of a building.

Eave Height: The vertical dimension from the finished floor level to the top of the eave strut.

Eave Strut: A structural member, located at the eave, used for supporting the roof panels and the wall panels.

Edge Distance: The perpendicular distance between the plate edge and the center of the bolt hole.

End Bay: The first or last bay in the building, as opposed to interior bay. It is the spacing between the outside face of the outer flange of the endwall columns and the centerline of the first interior column.

End Lap: A term used to describe the lap at a purlin location where the end of one panel overlaps the end of the panel below it.

End Lap Mastic: Sealant, in extruded bead form, used to seal end laps of roof panels for weather-tightness. Also called Bead Mastic.

End Plate: A plate welded at the end of a member.

Endwall: A term used to describe the entire composition of a building end. See Post & Beam Endwall or Rigid Frame Endwall.

Endwall Roof Extension: Roof cantilevered beyond the endwall.

Erection Drawings: Drawings and erection instructions which identify all the individual components in sufficient detail, to permit the proper assembly of all parts of the metal building system furnished by the seller

Expansion Joint: A weather-tight joint across the width of the building allowing for expansion and contraction.

Exterior Mounted: A girt system where the girts are mounted outside the columns and are attached directly to the outside column flange. Also called By-pass Mounted.

Fascia: An accessory whose function is to enhance the appearance of a wall. Also used to cover the eave or gable of a building.

Fin Neck Bolt: Flat dome headed bolt used in framed openings, fascias, and mezzanines.

Finished Floor: Top of the concrete slab or the finished concrete surface.

Fixed Base: A column base that is designed to resist rotation as well as horizontal or vertical movement.

Flange: The projecting edge of a structural member.

Flange Brace: An angle member extending between girts or purlins to the inner flange of columns or rafters respectively, to provide them with lateral support and stability.

Flashing: A sheet metal closure used to provide weather tightness in a structure.

Flush Mounted: A girt system where the outside flanges of the girts and columns are flush. The girts are supported by the use of girt clips bolted to the column webs.

Footing: Reinforced concrete base that provides support for a column.
Framed Opening: Framing (headers, sills, and jambs) and flashing which surround an opening in a building. Usually provided to accommodate field installed accessories such as sliding doors, roll-up doors, etc.

Framing: Primary and secondary members (columns, rafters, girts, purlins, brace cables, etc.) which when connected together make up the skeleton of a structure to which the covering can be fastened.

Gable: The triangular portion of the endwall of a building directly under the sloping roof and above the eave height line.

Gable Angle: An angle fastened to the purlins at rake for the attachment of endwall sheets.

Gable Trim: A flashing designed to close the opening between the roof panels and endwall panels.

Galvanized: Steel coated with a layer of zinc for corrosion resistance.

Girt: Secondary horizontal member attached to the mainframe columns. Girts normally support wall panels.

Girt Clip: Angle clips used to connect girts to the endwall columns.

Grout: Non-shrinking sand and cement based mixture used under base plates to obtain a uniform bearing surface.

Gusset Plate: Steel stiffener plate used to help distribute load at a connection.

Gutter: Pre-formed light gauge metal channel at the roof, along the sidewalls, or in valleys of multi-gabled roofs for the collection of rainwater.

Hair Pin: Reinforcement bars used in distributing forces from the column foundation to the floor slab.

Header: A horizontal member over an opening in a wall.

High Strength Bolt: Any bolt made from steel having a tensile strength in excess of 690 megapascal (MPa). Some examples are: ASTM A325, A354, A449 and A490.

Hot Rolled Shapes: Steel sections (angles, channels, I-sections, etc.), which are formed, while in a semi-molten state at the steel mill, into a shape having standard dimensions and properties specified by relevant standard specifications.

Impact Load: A dynamic load resulting from the motion of machinery, crane ways, elevators and other similar moving forces.

Interior Bay: The distance between the centerlines of two adjacent interior rigid frames.

Jack Beam: A primary horizontal member used to support another beam, truss or rafter.

Jib Crane: A cantilever boom or horizontal beam with a hoist and trolley.

Joist: A horizontal member for supporting the decking of floors or roofs.

Knee: Intersection of the column and rafter, also referred to as haunch.

Lean-To: A structure dependent upon another structure for partial support and having only one slope or pitch.

Lintel: A beam (either concrete or steel) in masonry walls placed above doors, windows or openings to support masonry above.

Live load: Any variable load that results from intended use of the structure during its life time. This includes all loads that the structure is subjected to during erection, maintenance and usage throughout the lifetime of the structure. The live load is specified by the applicable building code for which the structure is designed.

Loads: Anything that causes a force to be exerted on a structural member. Examples of different types of loads are:

a) Dead Load e) Wind Load
b) Live Load f ) Crane Load
c) Impact Load g) Collateral Load
d) Seismic Load h) Auxiliary Load

Longitudinal: The direction parallel to the ridgeline.

Louver: A wall opening provided with slanted blades, fixed or movable, to allow flow of air inside the building.

Mezzanine: An intermediate floor within a building above the ground floor that occupies all or part of the building floor area and consists of columns, beams, joists, deck panels and edge trims to receive reinforced concrete.

Moment: The tendency of a force to cause rotation about a point or axis.

Moment Connection: A connection designed to transfer moment, as well as axial and shear forces, between connecting members.

Monorail Beam: A single beam support for a material handling system. It is normally a hot rolled “I” beam.

Mezzanine Load: is the dead load of the mezzanine framing, including all finishes, in addition to the live load applied on the mezzanine according to its occupancy and usage classification.

Mono-Slope: A building sloped in one direction
Multi-Gable Buildings: Buildings consisting of one or more gables across the width of the building.

Multi-Span Buildings: Buildings with interior columns.

Panel: A piece of roof or wall sheeting. See also Sheeting.
Parapet Wall: That portion of the vertical wall which extends above the roof line at the intersection of the wall and roof.

Pilot Door: A small access door within one leaf of a sliding door. Also called Wicket Door.

Pin Connection: A connection designed to transfer the axial and shear forces between connecting members, but not moment forces.

Pinned Base: A column base that is designed to resist horizontal and vertical movement, but not rotation.

Pitch (Hole): Distance between center lines of holes along longitudinal axis of plate.

Pitch (Roof): Slope of the roof

Plan: Details of a building as viewed from the top.

Portal Frame: Column and beam bracing used in lieu of standard diagonal cable bracing to provide clear access.

Primary Framing: The main load carrying members of a structural system, generally the columns, rafters, and/or other main support members.

Primer Paint: The initial coat of paint applied in the shop to the structural framing of a building for protection against aggressive environmental conditions during shipping and erection.

Purlin: A horizontal secondary structural member, bolted to the rafters, which transfers the roof loads from the roof covering to the primary frames.

Rafter: A primary beam member supported on columns.

Reactions: The resisting forces, at the column bases of a frame, holding the frame in equilibrium under a given loading condition.

Ridge: The peak, or highest point of a gabled building, which describes a horizontal line running the length of the building.

Ridge Ventilator: The ventilator used at the ridgeline.

Rigid Frame Endwall: A system of endwall framing where the main interior frame is used at the endwall mostly for the purpose of future expansion.

Risers: The vertical rise of the steps of a staircase.

Roll-Up Door: A door, which opens vertically and is supported on a shaft or drum and runs along vertical tracks.

Roof Curb: Weatherproof flashing used on roofs to support power ventilators or ducting. Roof curbs can be fiberglass or sheet metal.

Roof Monitor: Raised gable, or portion of the main building, located at the ridge, to allow lighting and ventilation.

Roof Slope: The angle that a roof surface makes with the horizontal. Usually expressed in units of vertical rise to 10 units of horizontal run.

Sag Rod: A tension member used to limit the movement of a girt or purlin in the direction of its weak axis before the installation of sheeting.

Secondary Framing: Members, which carry loads to the primary framing. In metal buildings this term includes purlins, girts, eave struts, flange braces, etc.

Seismic Load: The assumed lateral load acting in any horizontal direction on the structural system due to earthquakes.

Self-Drilling Screws (SDS): Fasteners, used for attaching panels and trims to girts and purlins, which drill their own holes and eliminate the pre-drilling operation.

Self-Tapping Screws (STS): Have the same function as SDS but need pre-drilled holes.

Sheeting: Profiled metal panels.

Shims: Small steel plates used for leveling base plates or for packing between structural members.

Shop Details: Drawing details for fabrication of parts and assemblies.

Side Lap: A term used to describe the lap at the side or lengthwise direction of panels.

Sidewall: A term used to describe the entire composition of a building side, which is parallel to the ridge.

Sill: The bottom horizontal member of a door or window opening.

Skylight: At translucent panel used at the roof to transmit natural light. It is usually made of fiberglass.

Slats: Flat strips used in the shutters of roll-up doors.

Sleeve Nut: A long nut normally used to join two brace rods of the same diameter together. Also known as Coupling.

Sliding Door: A single or double leaf door, which opens horizontally by means of overhead trolleys or bottom wheels.

Soffit: The underside covering of any exterior portion of the metal building such as canopies, sidewall and endwall roof extensions.

Soil Pressure: The load, per unit area, a structure will exert, through its foundations, on the soil.

Space Saver: Building with a single gable clear span and straight columns. Wall girts are flush mounted.

Span: Distance between the supports of beams, girders or trusses. In a pre-engineered, building distance between interior columns.

Splice: The connection between two structural members.

Step in Eave Height: The condition where a lower building is attached to a higher building at the endwalls, resulting in one building with different eave heights at each end. Sometimes called Roof Transition.

Stiffener: Plate welded to a member to increase strength of the web or to provide continuity at connections.

Load carrying members. May be hot rolled sections, cold-formed shapes, or built-up sections.

Tapered Member: A built-up plate member consisting of flanges welded to a web of variable depth.

Throat: Minimum width of the ventilator air inlet.

Thrust: A horizontal component of a reaction

Truss: A structural member, made up of several individual parts welded or bolted together, designed to carry a tension or compression force with the complete structure acting as a beam.

Tube Column: A vertical structural support member made of a hollow square tube. Normally used as an interior support column in Multi-Span buildings or mezzanine floors.

Under Hung Crane: Bridge crane hanging from beams, rather than supported on beams.

UL Rating: Underwriters Laboratories certification rating for reliability and quality.

Uplift: Wind load on a building, which causes a load in the upward direction. See also Suction.

Valley Gutter: A channel used to carry off water, normally from roofs of multi-gabled buildings.

Web: That portion of a structural member between the flanges.

Web Member: A structural member vertically or diagonally interposed between the top and bottom chords of a truss.

Width Extension: A Lean-To connected at the sidewall of a main building and having a roof with the same slope and level of the main building. See Lean-To.

Wind Column: A vertical member supporting a wall system designed to withstand horizontal wind loads usually at endwalls.

Wind Load: A loading representing the pressure exerted on a structure by a given wind velocity. A load caused by the wind blowing from any horizontal direction. A basic wind speed is specified from which a velocity pressure is calculated. This velocity pressure and peak combined pressure coefficient are used to determine the design wind pressure according to the following equation:

q = 2.456 X 10 -5 V2 H 2/7 where
q = velocity pressure in kilonewton per square meter (kN/m2)
V = specified basic wind speed in kilometers per hour (km/h)
H = mean roof height above ground in meters (m) (H must be greater than or equal to 4.6m)

Note: Eave height may be used instead of mean roof height if roof slope is not greater than 10o (1.76:10)

“Z” Section: A member formed from coiled steel stock into the shape of a block “Z”. Usually used for purlins and girts.