AASHTOAmerican Association of State Highway and Transportation Officials
A 36 ASTM designation for yield strength of structural steel in psi (36,000 psi).
Access door Any door through an assembly structure usually providing access to a mechanical or electrical circuit within the assembly structure (usually flush with screw type openers)
ADA Law Americans with Disabilities Act
Admixture A material which is added to the standard concrete mixture to change and alter the concrete design mix.
AFF Above finished floor
Air handler A piece of mechanical equipment containing a blower and coils for the heating and or cooling of air in a HVAC circuit.
Anchor bolt A threaded bolt-embedded in concrete or masonry construction for the attachment of other structural assemblies.
Annealed glass Ordinary window glass that is cooled slowly to eliminate stresses in the material.
ANSI American National Standards Institute
Angle of repose The internal friction and cohesion of soil allowing it to assume a natural angle at rest.
ASTM American Society for Testing and Materials
Backer rod A flexible plastic foam material inserted into a joint to provide a limit to building caulking.
Backfill Soil that is used as fill around an excavation, against a foundation, or in site engineering design to establish a finished grade.
Backhoe A piece of excavation equipment used to dig with by drawing a steel bucket towards the operator of the equipment. Buckets are designed in one cubic yard increments.
Baseplate A steel plate which a steel column bears upon allowing for a distributed load to the substructure of a building. Baseplates are fastened to substructure with the aid of anchor bolts.
Batch plant A concrete mix batching plant that establishes all the proper proportions of ingredients that comprise a concrete design mix.
Base line A virtual line which establishes the point of departure for all building layout in the field.
Back check valve A valve inserted into a water line circuit to prevent the back flow of water during flow operations.
Balloon framing A framing method of installing continuous studs for greater than one story in height.
Ballast A round washed gravel or stone used to weight down a roofing membrane assembly
which is not attached to the structure of the building.
Backset A dimension used in hardware applications indicating the distance from the edge of a door to the center of the door-opening device. (doorknob, lever, etc.)
Beam A structural member that accepts loads from joists, slabs, and decks. Part of a hierarchy of structural members consisting of slab/joist/beam/girder/column. Usually supported at its ends and spanning between columns, girders, or footings.
Bed joint The horizontal mortar joint in masonry construction.
Bearing A surface or point at which a load is transferred from one building element to another.
Bedrock A solid, uniform, layer of rock of known density.
Bentonite A colloidal clay that will swell to several times its volume when exposed to water.
Benchmark Any established location of elevation used as a reference.
Benched excavation An excavation procedure that utilizes platforms to stabilize the slope of a deep excavation.
Bird screen A galvanized or stainless steel wire mesh to prevent birds from entering HVAC and other intakes and openings located at the closure assembly of a building.
Block A short term used to describe concrete masonry units.
Block reinforcing The insertion of steel reinforcing rods and or steel wire truss reinforcing in a block assembly wall.
Boiler A piece of mechanical equipment for the production of hot water used in heating.
Brick bond The pattern of brick in a masonry wall.
Brick course The horizontal layer of brick masonry.
Brick shelf A constructed or inserted bearing surface for brick masonry to sit upon.
Bricklayer A tradesmen or mechanic who lays brick and CMU,s.
Brick ties A wire or sheetmetal strip used to connect brick work to another assembly part enabling the brick to move independent of the tied assembly.
Branch circuits A secondary circuit of electrical distribution for power and lighting to individual building areas and or rooms.
Bulkhead A term used to describe a break in concrete formwork that will be continued at another time. Also a mechanism to discontinue formwork with a predictable designed procedure.
Busbar A solid bar of aluminum or copper conductor for primary distribution of electric service throughout a building.
Busduct The assembly structure surrounding, isolating, and containing the busbars.
Caisson A solid cylindrical concrete structure which is placed through unsatisfactory soil to solid bearing (usually rock) upon which the substructure and superstructure will be built.
Cable railings Temporary steel cables strung between steel or concrete columns for the protection of workers at the edge or around openings in buildings while under construction.
Cable tray A steel tray for the containment of computer, telephone, and fiberoptic cable that is either hung from the floor above, or inserted into a floor assembly.
Cage A term used to describe a cage of reinforcing bars which have been prefabricated for columns and or beams and girders in concrete construction.
Cant strip A strip of inclined material used to assist the drainage of water away from a parapet wall.
Cap coping A term used to describe the course covering material used over a parapet wall or at the top of an assembly wall.
Cap flashing The flashing which occurs at the cap coursing of a wall to prevent the entry of water.
CMU Concrete masonry unit
Carpenter A mechanic who constructs things of wood.
Caulking A term that refers to any elastic sealant used in construction.
Cavity wall The term used to describe a masonry assembly wall where the outer wythe of masonry is separated from the inner masonry assembly by a continuous air space.
Casework The term used to describe all cabinet, counter, and built in furniture work in a building.
Cast in place Concrete that is formed and placed (poured) on site.
Centrifugal chiller A piece of HVAC equipment which utilizes centrifugal force to assist the phase change cooling process of water which in turn is circulated throughout a chilled water circuit to individual air handlers.
Chase A constructed space within an assembly (wall, floor, or ceiling) for the passage of mechanical, plumbing, or electrical circuits
Chamfer The easing of an edge of a solid material at 45 degrees to each face.
Channel section A structural steel section with a cross section in the form of a “C”.
CI Cast iron.
Cistern A reservoir or tank for holding water or other fluids.
Circuit Any complete movement of fluid, air, gas, or electricity through a pipe, duct or conductor.
Closer A piece of door hardware which enables a door to close and latch by itself.
Clevis Hanger A steel “U” shaped hanger for the support of piping off a structural floor
which allows for thermal expansion and pitch adjustment in piping installations.
Cohesive soil A soil consisting of silt and clay where the soil particles tend to stick together producing a sticky plastic soil characteristic.
Cold-formed steel Sheet steel which is formed at room temperature into its final shape.
Column A vertical structural member designed to take primarily a compressive load.
Column splice The joining of two columns on axis with the aid of steel plates, or a welded connection.
Column bay The total floor area exerting a load on a particular column and or the regular spacing of columns in a structural frame.
Compaction The mechanical process of compacting soil, backfill and borrow fill operations with the aid of mechanical means.
Composite The joining of two or more materials into a structural whole.
Composite deck Corrugated and upset steel decking used as a lost form in the placement of concrete that provides the tensile strength to a concrete floor assembly.
Compound (taping) A mixture of plaster and other materials used in the process of covering joints and corners in gypsum board surfaces and assemblies.
Concrete A mixture of portland cement, aggregates, and water in predetermined designed quantities which cures and hardens to form a structural material with good compression strength.
Concrete duct bank A series of electrical conduit, cables, and or buss bars encased in concrete and usually buried under the ground.
Concrete pump A piece of construction equipment (usually a truck designed for this purpose) which has the capacity to pump concrete through a series of joined pipes and flexible connections to a point of placement.
Concrete placement The act of placing concrete into formwork.
Concentrated load A load which has a pointal rather than distributed characteristic on a structural member.
Conductor A material which will allow the passage of electric current.
Condensate gutter A gutter located at the bottom of a window or skylight to collect condensate, which forms, on the inside of glass. The condensate is in turn weeped to the exterior of the assembly through the frame.
Control joint A designed joint that enables the controlled distribution of forces occurring in assemblies.
Coped The modification of one member or surface to fit into or on another member or surface.
Coursing The horizontal layer of any masonry module. The number of courses in a vertical dimension of a wall.
Creep A permanent deformation in a material due to prolonged structural stress or loading over time.
Crushed stone Aggregate of stone that has irregular sides usually of one dimension or sieve size.
Curing The hardening of concrete or other wet materials through evaporation, hydration, or chemical reaction.
Curing compound A material which is sprayed over newly placed concrete forming a film that retards the dehydration of the concrete allowing it to cure over a longer period of time.
Curtain wall A non-load bearing exterior closure wall assembly that is attached to the structural frame of a building.
Cylinder In hardware terms: the cylinder shaped mechanism, which contains the actual keying slot and locking code for locking a door.
Damper A mechanical shutter or flap which controls the flow of gasses through a circuit.
Dampproofing An asphaltic coating applied to the outside surface of a substructure to inhibit the passage of moisture.
Dead bolt A locking mechanism for a door or window, which locks a door independently of the latching mechanism in a more secure manner.
Dead load The total weight of a structure, its assemblies, components, and mechanical systems.
Diffuser A mechanism, usually louvered, for the distribution of air at the terminus of a HVAC circuit.
DW Distilled water.
Door buck The frame of a door consisting of the head and jamb sections connected together as a single assembly (usually a hollow metal section)
Dowels In terms of building construction: a short piece of reinforcing rod used to join two separate parts of a concrete assembly together as a whole.
Drift pin tapered steel rod used by ironworkers to align bolt holes in structural steel for eventual fastening.
Drip pan A fabricated sheetmetal pan used to collect condensate from a piece of mechanical equipment and drain it away from other assemblies, equipment, or electrical circuits.
Drywall A term used to describe gypsum board wall construction.
Duct A fabricated hollow conduit for the containment of a HVAC or electrical circuit, usually made of sheet metal.
Efflorescence The powdery residue of salts which has leached out of brick masonry at the surface of a building.
Elastomeric A rubber like material which has a predictable size and shape within its’ stress level.
Emergency generator An engine using internal combustion to drive a generator producing a limited supply of electrical power to a building.
Emergency power Dedicated electrical circuits within a building which are connected to the main power supply as well as the emergency generator of electrical power.
Emergency switch A switch that is separate from any piece of mechanical or electrical equipment used to break an electrical circuit to that piece of equipment. The switch must be located in plain sight at or near the piece of equipment.
Expansion joint A constructed joint in an assembly allowing for movement of that assembly in a controlled location, and in a controlled failure.
Fabricator The contractor or company that prepares, numbers, and documents structural steel for erection in the field.
Face brick The brick masonry used as the exterior of façade of a building.
FAI Fresh air intake.
Fan room Any room or space dedicated to air handling equipment, which contains blowers and or fans.
Fatigue The continuous stressing of a material usually in bending leading to the eventual failure of that material.
Fibrous admixture Short lengths of fiber added to concrete to increase it’s tensile strength.
Filter fabric A woven synthetic fabric used as a screen to prevent the passage of sand and silt while allowing for the passage of water.
Fire damper A damper inserted in ductwork to prevent the passage of smoke and fire through a fire rated assembly.
Fire stop A material used to block the passage of smoke and fire in and around a penetration through a fire rated assembly.
Fireproofing A noncombustible material applied directly or indirectly around a structural steel element to inhibit the passage of excessive heat caused by a fire.
FR (fire rated) A rating by the ASTM for any materials performance, under fire conditions, to resist the passage of fire and heat.
Final acceptance The last stage in the commissioning of a building for its’ intended use, given by the Owner of the building to the general contractor.
Flame spread rating A measure of the time it takes for fire to spread across the surface of a combustible material based on ASTM E84.
Footing The part of a substructural assembly that allows the transfer of load to the soil for the support of the building.
Footing drain A drain, usually a porous or perforated pipe, which extends around a buildings footings for the purpose of taking ground water away from the substructure to a distant drainage circuit at a lower elevation.
Foundation walls The vertical walls of a substructure, which transfer their loads to footings.
Forms Structures used in concrete placement to give form to the concrete and hold it in that form until such time as the concrete sets and cures to a predetermined strength. Forms may be constructed of wood, plastic, steel, or soil.
Form ties Steel rods that hold two separate forms apart to facilitate the placement of concrete through the curing process or until the forms are stripped.
Floor plate The entire floor area and or assembly of any one story of a building.
Flange The two identical thicker members of a wide flange beam or column separated by the web of the section.
Flashing A continuous sheet of impermeable material used to prevent the infiltration of water into the interior of a building. Flashing may be made of metal, plastic, rubber, or impregnated paper.
Flagman A person who warns of construction operations, danger, caution, and general hazardous conditions by the use of flags of signs.
Flexible conduit A conduit, either electrical or mechanical, which allows for differential movement between two different pieces of equipment or circuits while maintaining the integrity of that circuit.
Furnace A mechanical piece of equipment for the production of hot air through combustion of a fuel, heat exchanger, and or radiant electric coils.
Fusible link A metal tie in a fire warning, prevention, or suppression system which will melt at a predetermined temperature initiating that systems operation.
Gauge The measure of thickness of wire (AWG), sheet metal, or hollow metal work. The lower the gauge number the thicker the material.
General Contractor The contractor having overall responsibility for the Construction Contract, the hiring of subcontractors, job safety, job procedures, and the coordination of the work.
Girder A large structural member usually fabricated of smaller structural elements, which receives loading primarily from beams.
Glazing The procedure and act of installing glass into frames.
Grade beam A beam which spans a grade condition while bearing on a pier, footing, or pile cap.
Grout A high strength mixture of portland cement, aggregates, and water with a high slump.
Ground A piece of material attached to a wall, floor, or ceiling as a guide for the application of plaster, terrazzo, or other finished materials. Grounds are also used as leveling points in all wet trades.
Grounding rods Metal rods that are driven into the soil to a predetermined depth for the purpose of grounding the building against lightning strike.
Gypsum board A construction board of gypsum (hydrous calcium sulfate) sandwiched between two layers of craft paper or other fibrous material used as interior or exterior surfacing in a wall or ceiling assembly. Also called drywall and or plasterboard.
Hangers The name given to any device used to hang a mechanical piece of equipment, pipe, duct, and ceiling, off the underside of a structural frame or floor assembly above.
Hard hat A hat constructed of a rigid material and designed to take a predetermined impact load for the protection of the head. It must be ASTM and OSHA approved.
Hasp A simple bar and ring piece of hardware that allows for the locking of a door or gate by inserting a pad lock through the hardware.
Hang a door The procedure for attaching a door to its frame and adjusting it to open, shut, latch and lock properly.
Head joint The vertical joint of mortar in all masonry bonding.
High-strength bolt A steel bolt used to connect steel structural members together through friction.
Hollow metal The term used to describe the cold formed sheet steel used in the construction of doors, door frames, borrow light frames, and some window frames.
Hook A semicircular bend in a reinforcing bar that enables it to resist a pulling loads anchoring it securely in concrete. Used to tie two separate concrete placements together.
Hopper A bin or container that holds a reserve of dry material such as premixed mortar for controlled release as required.
Horizontal truss reinforcing A wire truss which is placed in a bed masonry joint of mortar for the purpose of reinforcing the masonry assembly at a predetermined regular interval. Usually every six courses of common brick and or every two courses of block.
Honeycombing Excessive areas of voids and or air pockets present in concrete placement that will diminish the strength of that placement area.
Hydrostatic pressure A uniform pressure exerted on a surface by ground or standing water.
Hygrosopic The ability of a material to absorb moisture.
Insect screen A screen which will prevent the passage of insects into a building assembly.
Invert The elevation of the inside diameter of a pipe..
Ironworker A skilled mechanic who erects and installs structural steel building frames.
Jacket A metal covering around a pipe or piece of mechanical equipment.
Joint sealer Caulking compound.
Joist The primary horizontal member, which transfers a floor or roof load to beams, girders, and columns.
Junction box A metal or plastic box allowing for the pulling and splicing of electrical wiring and or terminus of an electrical circuit in an assembly.
Key A formed slot depression in concrete interlocking the joining of two separate concrete placements.
Keyed A joint that has a key interlock. A lock that has been commissioned is said to be “keyed.”
Kick board A temporary board used at the perimeter of a building or opening for protection from falling objects which might be kicked off a slab or floor plate onto workers below.
Knee wall Any short wall assembly.
Laid up A term used to describe the work done or being performed on a masonry wall installation.
Laminated glass Two sheets of annealed glass bonded to a plastic inner layer. A form of safety glass.
Lamp The actual bulb or encased gas source producing light in a fixture.
Laser level An instrument producing a laser beam which is used in leveling, layout, and Plumbing up walls and structure.
Lateral bracing Structural bracing against loads produced in the horizontal direction or parallel to the ground plane.
Latch A piece of door or window hardware, which secures it in the closed position but does not lock it.
Layout Marking the actual field location of any part of a building excavation, assembly, structure, mechanical, plumbing, electrical, et al, and locating that part on and within the building under construction.
Level A surveying instrument used in establishing a datum for the location of elevations and plumb vertical surfaces.
Leveling screws Any screw or bolt used to level a piece of equipment or structural column base plate.
Lift In masonry terms, a movement of scaffolding to enable the next vertical section of wall to be laid up.
Line current Alternating electrical current of 110 volts or more.
Light-gauge steel stud A cold formed steel stud made of sheet metal of 22 gauge to 16 gauge in thickness.
Lightning point The terminus of a grounding system, usually the highest point on a building or structure and made of a solid conductor such as copper or aluminum.
Lintel A structural member that will carry a load across a window or door opening.
Live load The total weight of people, books, furniture, office equipment, vehicles, snow and any other materials not a permanent part of the building structure.
Logged The process of recording a receipt of a construction document or the entry and exit of personnel into a construction site.
Lost formwork Formwork used in the placement of concrete or backfill that is designed to be buried or incorporated into the structure and not removed.
Loose lintels Usually steel angles used over window and door openings to support masonry work above bearing on masonry and not connected to the structure of the building.
Lumber A grading of wood which includes materials less than 4 inch and greater than 2 inch in thickness.
Mason A mechanic who places and finishes concrete.
Masonry Brickwork, blockwork, and stonework.
Manifest The document which list the contents of a truck, ship, plane or train.
Main feeder In electrical work, the primary conduit for current.
Master In terms of hardware, the keying of locks which will allow a single key to operate most locks. A grand master will operate all locks in a keying sequence.
Mechanical trowels A piece of concrete finishing equipment which has three or four steel trowels attached to an internal combustion engine and produces a concrete finish ready for hand finishing.
Metallic lathers Experienced workers who install steel reinforcing rods, welded wire fabric, pretensioning cables, and lath in concrete and plaster work.
Membrane A sheet of material either built up or single ply which is impervious to the penetration of water.
Millwork Prefabricated wooden components of a building i.e.: windows, doors, cabinets, moldings, stairs, etc.
MO Masonry opening.
Modulus of elasticity The stiffness of a material derived from measuring the elastic deformation of a material under load stress, then dividing the load stress by the deformation.
Monument A permanent surveying mark placed in the ground or onto bedrock indicating elevation, and location of that point as a reference.
Mortar A mixture of cement, sand, lime, and water used to join masonry units together.
“Mud” A common name for mortar used by bricklayers.
Mud slab A nonstructural thin slab of concrete placed directly on the ground for purposes of providing a hard dry surface to work upon
Neoprene A synthetic rubber material which can be molded or extruded into shapes. (Polychloroprene)
Nominal The approximate size and or dimension of a material or building module.
Nosing The extended part of a stair tread beyond the riser.
OC or (o/c) An abbreviation for “on center”. Used in dimensioning to indicate on center dimensions of members, columns, windows, etc.
Occupancy group A category establishing the intended use for a building. The act of occupying the building for its intended use by the Owner.
Offset To move or dimension something off center for purposes of installation, access, and or clarification.
Open web joist A fabricated structural steel truss usually made of steel angle sections and or bar members.
OSHA Occupational Safety and Health Act.
Oxidation The rusting of steel or iron.
Parapet The projection of an exterior wall assembly above the roof.
Perforated pipe Pipe (PVC) which has been perforated for underground drainage collection.
Penthouse A part of the superstructure above the roof.
Pipe plugs Plugs used to close off a pipe temporarily for the purpose of pressure testing.
Pipe insulation A preformed rigid insulation for piping.
Plastic laminate A thin sheet of synthetic material used as a surfacing for counter tops, doors, and walls.
Platform A landing in a flight of stairs, usually between floors.
PMR Protective membrane roofing. A roofing membrane installed under the roof insulation as a protective measure against temperature differentials and UV light.
Porous concrete pipe Concrete pipe which is porous allowing for water to enter for underground drainage collection.
Pointing The application of mortar or high strength grout to a joint or hole in masonry or concrete.
Pour stop The construction of a wood or metal stop for the control placement of concrete usually at the edge of a slab. In composite deck construction this is a cold formed steel angle which becomes part of the floor slab as a lost form at its edge.
Pour The common term for the continuous placement of concrete in a form.
Precast concrete Concrete that has been cast and cured prior to its installation in or on a building assembly.
Prepared backfill A backfill material that has been designed for its intended use by specification.
Pressure test A test of plumbing piping for leaks.
Project Manager A person or construction firm in direct charge and coordination of all contractors involved with supplying, fabricating and building a project.
Puddle weld The weld used in fastening the composite steel deck to the structural steel frame.
PVC Polyvinyl chloride.
Quick set cement Type III cement which when used in a concrete mix, sets up in a short period of time.
Quantity survey A list of all materials which go into the building of a structure.
Raker A diagonal brace for supporting sheeting of an excavation.
Reglet A preformed slot in concrete or masonry for the eventual installation of flashing or membrane.
Rebar A common name for steel reinforcing rods placed in concrete.
Refusal The point at which the desired bearing condition is reached in soil or rock.
Rise A difference in elevation.
Riser The vertical part and dimension to a stair. Also a vertical run of plumbing, electric wiring, and or HVAC ducts.
Riggers The people who secure straps, leads, cables, and ropes to a load for the purpose of lifting that load into place on a building.
Roofer The contractor who supplies and installs roofing materials.
Roofing The materials that are applied to a roof to make it watertight.
Roughing in The installation of electrical plumbing and mechanical work which will be buried within an assembly structure such as a wall, floor or ceiling.
RO The rough opening dimension for a door, window, or piece of equipment.
Rodded The process of distributing the concrete mix in a test cylinder or slump cylinder. The concrete is “rodded” using a steel rod in an up and down movement.
Running bond Brick bond consisting of stretchers with head joints at the mid point of the coursing below.
Relamp The act of reinstalling light bulbs, lamps, and various luminaries.
Safing The installation of fire resistant material into a space, hole, opening, etc. through a fire rated assembly to insure the integrity of that assembly.
Safety glass Laminated or wired glass which will hold and maintain the shards of glass in place when broken.
Safety harness The harness worn by Ironworkers and steel erectors securing them to the structural frame with a safety line. OSHA requires this of all workers who erect structural steel and or are working on any structural frame prior to the installation of floor plates.
Saddle The part of the doorsill that spans the sill to floor construction joint and or is used as a stop for the bottom of the door. In interior doors the saddle is a closure piece from the floor to the door bottom (sometimes called a sill or threshold).
Sash The frame that holds the glass of a window and in turn is part of the window assembly.
Segregation The separation of the components of a concrete mix during placement due to improper handling and or vibration.
Set The curing of concrete. The act of setting a nail by recessing it beyond the face of the material it is nailed into.
Setting block In glazing, a small synthetic block of material used to support the glass at its base bearing surface.
Service drop The main feed of electric service from a utility to a building .
Service slab A 4” high slab of concrete placed over the floor slab as a pad for the installation of a piece of mechanical equipment
Shaft A vertical aligned series of penetrations through a buildings floor plates for elevators, ducts, et al.
Shaft liner Gypsum board which has been fire rated and designed as an assembly for installation as a shaft wall.
Shear stud A steel dowel which is welded to a steel girder, beam, or joist, as part of a composite concrete assembly. The stud engages the concrete floor with the steel structure.
Shop drawings Detailed drawings prepared by a manufacturer, fabricator, contractor, or installer for the purpose of insuring the proper fit of materials, assemblies, and equipment into the constructed assembly of a building.
Shotcrete A dense mixture of concrete designed to be blown from a high-pressure hose and nozzle via compressed air. Reinforcing filaments of fiber are either included or incorporated at the nozzle as part of the mix.
Shims Small pieces of blocking, usually wedge shaped, for aligning windows, doors, and equipment plumb and straight.
Shelf angle A steel angle attached to the structure of a building frame and carries the load of a brick masonry facing. Sometimes referred to as a relieving angle.
Shoring Temporary bracing and supports for structural reasons
Silencer Rubber inserts which when installed in a door stop allow the door to close with a minimum of noise. The silencers also provide positive pressure against the door while in the latched position.
Slenderness ratio A ratio of the height of a column to its cross sectional properties.
Slump test Usually referred to as the slump it is a test performed on the jobsite by a concrete testing laboratory. The concrete is placed in a cone shaped form and rodded to distribute the mix. The cone is removed and the wet concrete slumps. The slump of the concrete is measured against the original cone form to establish its slump (usually 4” for most mixes)
Sleeves Preformed steel pipe or box sections placed in concrete formwork to create a hole through a concrete floor, wall, or slab.
Soil All excavated material exclusive of solid bedrock and organic matter that is divided into various classes and types.
Soils engineer A professional engineer who studies, engineers, and determines the bearing capacities of any given soil type, designed backfill, and or rock bearing capacity. The investigation of soil is performed by taking boring samples of the existing soil condition.
Soil line A waste pipe from a plumbing fixture.
Smoke purging The mechanical system required to remove smoke from a building atrium in the event of a fire. The removed gases are replaced with fresh air as part of the smoke purging circuit.
Spandrel The wall between the head of a window and the sill of a window on the next floor. The spandrel therefore spans between floors.
Spreader bar A temporary metal channel at the sill of a door buck which keeps it square until installation.
Splice plate A structural steel plate which joins two columns together at the flanges.
Stack A vertical column of gas; a vertical or pitched tube container for the removal of combustion gases in a building, piece of equipment, or vehicle.
Strike plate The plate located on a door buck jamb that receives the lock and latch when the door closes.
Static head The pressure created in a pipe by a column of water.
STC Sound transmission class. The index used to establish the resistance of an assembly for the passage of sound.
Steel Decking A corrugated cold formed metal sheet, which is used to span across joists, beams, and girders as part of a floor or roof assembly.
Steel fabricator One who fabricates structural steel to the specifications of the construction documents.
Steel pan A preformed steel pan used as a concrete form for composite concrete stair treads. Steel pan stairs have concrete treads and platforms with steel risers, stringers, and railings.
Staging A construction procedure for the storage and or fabrication of material on a job site.
Stiffener plate A steel plate usually welded to the web of a beam or girder to support a concentrated load or reinforce the web at a cutout section.
Stirrup Reinforcing steel in a U or box section used to resist tensile stresses diagonally transferred through a concrete beam, girder, or wall.
Steam fitters Mechanics who are expert in the welding and installation of high-pressure water or steam pipe.
Stringer The supporting structural member of the treads and risers in a stair.
Stripping The procedure of removing formwork from concrete after the concrete has set.
Substructure The portion of a building which is below grade.
Superstructure The portion of a building which is above grade.
Superplasticizer An admixture for concrete which makes it more fluid without the addition of more water.
Switch gear A high voltage (600 volts plus) switching mechanism and circuit breaker for distributing electric current throughout a buildings primary circuitry.
Taping The term used for the application of taping compound, tape and beads to finish the surface and edges of gypsum board (drywall) construction.
Tempered glass Annealed glass that has been cut to size and heat-treated to produce a glass that has a strength of 15,000 psi.
Tensile stress Stress resulting from stretching a material.
Telltale Lightweight cloth or plastic tape that has been tied to cable railings at the edge of a floor plate identifying the edge of a building. (a warning device)
Temporary protection Any barrier, warning device, railing, covering, etc., necessary and or required on a construction site for the protection of human life and any protection connected with the building process.
Test cylinders Sample cylinders of concrete taken from each truck delivering concrete from a batch plant. The cylinders are cured and tested in a laboratory to verify the strength of the designed mix.
Terrazzo A wet floor finish material made up of cement, sand and marble aggregate which is ground smooth and polished after it has cured.
Thin set terrazzo A wet floor material made up of epoxy, marble dust, and marble aggregate which is ground smooth and polished after it has cured.
Thermal break A material with low thermal conductivity used to stop the passage of heat through and assembly.
Thrust block A solid concrete block placed at the juncture (change in direction) of a water line which has been buried, preventing the line from breaking due to pressure surge caused by a water hammer. Also, the blocking located at the bottom of a stair run which prevents stair stringers from sliding out of place.
Tieback A structural tie used to hold sheeting around an excavation by drilling the tie into the soil behind the sheeting and securing it through the sheeting as a tensile member.
Timber A piece of dimensional lumber over 4”x4”.
Tinknockers A common term for metal duck installers.
Tooling The act of finishing a mortar or caulk joint to the specified profile.
Topping A thin finished layer of concrete, asphalt, or soil.
Topping out The installation of the top most member in a buildings structural frame.
TOS Top of steel elevation.
Torque wrench A pneumatic wrench for tightening steel structural bolts to the proper tension specified for the connection.
Tremie A tube for the distribution of concrete in a controlled manner from the bottom of a form to the top. Tremie procedures are usually carried out through water or slurry displacing the liquid as concrete is placed.
UL label Underwriters Laboratory seal of approval based on accepted testing methods and results.
Ultra Violet (UV) Insolation (in coming solar radiation) in the UV wavelength that over time damages many materials exposed to the sun.
Unit dimension (UD) The actual dimension of a window, or door unit from the outside of the frame.
Underlayment The leveling and preparation of a floor with hard board, patching, or any surfacing material for the application of a finish flooring system or material.
Uniform load A load which is distributed over a structural member, floor, or column without any concentrated loading condition. (pounds per square foot; pounds per square inch)
Unit masonry A masonry module designed to be repetitive and modular with other masonry units.
Upset Any material that is raised above its primary surface yet interagal with that surface.
Valley A trough formed at the intersection of two sloping planes.
Vent stacks The pipes connected to soil lines which allow sewer gasses to escape through to the roof or ground surface. The vent pipe also prevents plumbing traps from siphoning off.
Vibrator A mechanical or pnumatic piece of equipment which vibrates at a predetermined rate and is used to compact soil or distribute concrete in formwork.
Vibration eliminator A mounting apparatus, springs or heavy resilient rubber, which isolates a piece of equipment from the building diminishing structure borne noise and vibration.
Vinyl Polyvinyl chloride that can be extruded into solid sheets, pipes shapes etc.
Voltage regulator An electrical device which is designed to eliminate any power surge or drop in current.
Waler A horizontal structural member in concrete formwork to which the form ties are attached.
Walking The phenomena of having a joint filler, building assembly part, railing, piece of equipment etc. move and or displace itself due to vibration, thermal loading, or gravity.
Waterstop A synthetic rubber ribbon installed between concrete construction joints to prevent the passage of water. Bentonite clay is also used as a water stop in substructura joints.
Water table The elevation of permanent ground water beneath the surface of the earth.
Web The part of a structural steel wide flange section that holds the two flanges apart.
Weep An opening that permits the drainage of water or condensation from a wall, assembly, window, skylight, or piece of equipment.
Welded plate girder A large structural steel girder made up of plates that are welded together.
Well points Drilled wells at regular intervals for the purpose of removing ground water from an excavation.
Wide flange section A structural member which is hot rolled into the shape of an H section or I section with two flanges and one web. The structural section which replaced the “I” beam American standard section.
Wind load The cumulative load on a building due to wind pressure (positive or negative).
Wired glass A safety glass manufactured with a wire mesh imbedded in the glass.
WWF Welded wire fabric.
Wythe A masonry dimensions which is one unit thick. The measure of a single masonry unit laid up.
X bracing Cross bracing of a permanent or temporary nature to resist lateral loading.
Yield strength The point in the stressing of a material when it is beyond its elastic limit and will not return to its original shape nor resist load.
Zero lot line The ability to build to a property or lot line without a set back.
Zoning ordinance A local law specifying what is permitted to be constructed on a piece of land within that zoning district, county, municipality, township, village etc.