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Main Library Construction Project: Construction Glossary

Updates on the new Main Library construction

Construction Glossary

from Construction Dictionary and Glossary of Construction Terms,, LLC


Metal securing device embedded or driven into masonry, concrete, steel or wood.

Anchor Bolt

Heavy, threaded bolt embedded in the foundation to secure sill to foundation wall or bottom plate of exterior wall to concrete floor slab.

Auxiliary Load

Any dynamic live loads such as cranes, monorails, and material handling systems.

Backing Bar

A welding aid used to prevent melting through of a joint when preforming, for example, a complete-joint penetration groove weld.

Bar Joist

Open-web, flat truss structural member used to support floor or roof structure. Web section is made from bar or rod stock, and chords are usually fabricated from "T" or angle sections.


Loadbearing member spanning a distance between supports.

Change Order

A written document which modifies the plans, specifications, or price of a construction contract.

Collateral Load

All additional dead loads other than the weight of the building, such as sprinklers, pipes, ceilings, and mechanical or electrical components.


Vertical loadbearing member.

Compressive Strength

Measures maximum unit resistance of a material to crushing load. Expressed as forceGlossForce.1040 per unit cross-sectional area, e.g., pounds per square inch (psi).

Corner Brace

Structural framing member used to resist diagonal loads that cause racking of walls and panels due to wind and seismic forces. May consist of a panel or diaphragm, or diagonal flat strap or rod. Bracing must function in both tension and compression. If brace only performs in tension, two diagonal tension members must be employed in opposing directions as "X" bracing.


A machine used to move material by means of a hoist. 2) A machine that can usually move and is used to lift heavy materials or to lift members that are to be erected in a structure.

Dead Load

Load on a building element contributed by the weight of the building materials.

Design Load

Combination of weight (dead load) and other applied forces (live loads) for which a building or part of a building is designed. Based on the worst possible combination of loads.


The line along the sidewall of a building formed by the intersection of the plane of the roof and the plane of the wall.

Eave Height

The vertical distance from finished floor to the eave.

Eave Strut

A structural member located at the eave of a building which supports a roof and/or wall panels.


A steel member such as a plate, bolt, stud, or bar cast into a concrete structure which is used to transmit applied loads to the concrete.


Term for a connecting device such as a weld, bolt, rivet, etc.

Fast Track

Method that telescopes or overlaps traditional design-construction process. Overlapping phases as opposed to sequential phases is keynote of the concept.


Condition of material under stress that has lost, to some degree, its power of resistance as a result of repeated application of stress, particularly if stress reversals occur as with positive and negative cyclical loading.


Lower extremity of a foundation or loadbearing member that transmits load to load-bearing substrate.


Beam, especially a long, heavy one; the main beam supporting floor joists or other smaller beams.


The ground elevation around a building.

Hot-Rolled Shapes

Structural steel sections which are formed by rolling mills from molten steel which can be angles, channels, W Shapes, S Shapes, etc.

Impact Noise Rating (INR)

Obsolete rating system for floor-ceiling construction in isolating impact noise. INR ratings can be converted to approximate IIC ratings by adding 51 points; however, a variation of 1 or 2 points may occur.


A device which holds work or pieces of material in a certain position until rigidly fastened or welded during the fabrication process.


Small beam that supports part of the floor, ceiling or roof of a building.

Joist Hanger

Metal shape formed for hanging on the main beam to provide support for the end of a joist.

Ledger Strip

Strip fastened to the bottom edge of a flush girder to help support the floor joists.

Live Load

Part of the total load on structural members that is not a permanent part of the structure. May be variable, as in the case of loads contributed by the occupancy, and wind and snow loads.


Force provided by weight, external or environmental sources such as wind, water and temperature, or other sources of energy.

Model Code

Building code, written and published by a building-official association, available to states, counties and municipalities for adoption (for a fee) in lieu of their own, e.g., Uniform Building Code, Standard Building Code, National Building Code.


A unit of measurement of Water Vapor Permanence (ASTM).


Column supporting a structure.

Pipe Bridge

A structural system where two joists are used to carry loads such as piping or ducts. The two joists have to have diagonal bridging and their top and bottom chords have to be laced together with structural members to provide stability for the whole structure

Pitch of Roof

Slope of the surface, generally expressed in inches of vertical rise per 12" horizontal distance, such as "4-in-12 pitch."


Forcing out of plumb of structural components, usually by wind, seismic stress or thermal expansion or contraction.


Measurement in height of an object; the amount it rises. The converse is "fall."


Fire stop material in the space between floor slab and curtain wall in multi-story construction.


Any opening or drain in the side of a structure, flat roof, or downspout for the drainage of rain water.

Shaft Wall

Fire-resistant wall that isolates the elevator, stairwell and vertical mechanical chase in high-rise construction. This wall must withstand the fluctuating (positive and negative) air-pressure loads created by elevators or air distribution systems.


Distance between supports, usually a beam or joist.


That portion of a building which is between the upper surface of any floor and the upper surface of the floor next above.

Story Drift

The difference in horizontal deflection at the top and bottom of a story.


Slender structural element that resists compressive forces acting lengthwise.

Tensile Strength

Maximum tensile stress that can be developed in a given material under axial tensile loading. Also the measure of a material's ability to withstand stretching.


Open, lightweight framework of members, usually designed to replace a large beam where spans are great.


Uniform Building Code -- document promulgated by the International Conference of Building Officials.

Vapor Retarder

Material used to retard the flow of water vapor through walls and other spaces where this vapor may condense at a lower temperature.

Weep Hole

Small aperture at the base of an exterior wall cavity intended to drain out trapped moisture.