A definitions - Building Terms Dictionary



A definitions - Do you know building terms starting with the letter "A"?



A frame
A building with a gable roof extending to the foundation

Abutment joint
A surface divider joint design to allow free movement between new and existing construction, or between differing materials.

Access Flooring
A raised finish floor surface consisting entirely of small, individually removable panel beneath which wiring, duckwork, and other service may be installed.

Accordion door
Door made of wood slats or fabric arranged to fold back and forth in the plane of the door frame.

Acoustic Ceiling
A ceiling of fibrous tiles that are highly absorbent of sound energy.


Acrylic
A transparent plastic material widely used in sheet form for glazing window and skylight.

Actual size
The true size of lumber in contrast to nominal size. The actual size of a 2 x 4 is 1 1/2" x 3 1/2".

Additive
Chemical added to concrete to alter its properties. Accelerators, retardants, and air entraining agents are example of additives.

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Admixture
A substance other than cement, water, and aggregates included in concrete mixture for the purpose of altering one or more properties of the concrete.

Aggregate
Inert particle, such as sand, gravel, crushed stone, or expanded minerals, in a concrete or plaster mixture.


Agricultural tile
Clay drain tile usually laid with open joints to permit water to enter.

Air duck
Pipe, usually rectangular or round and made of sheet metal, used to conduct hot or cold air in heating or cooling systems.

Air-entraining cement
A Portland cement with an admixture that causes a controlled quality of stable, microscopic air bubble to form in the concrete during mixture.

Air-to-Air heat exchanger
A device that exhaust air from a building while recovering much of the heat from the exhausted air and transferring it to the incoming air.

AISC
American Institute of Steel Construction.


Alkyd
A synthetic resin used as the base for surface coatings.

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Allowable span
Distance allowed between supporting points for various sizes of girders, joist, and roof rafters.

Alloy
A substance composed of two or more metals, or of a metal and a non-metallic constituent.

Amp
Measurement of electrical current.Designated I in formulas. Abbreviation as A.

Anchorage
The device that fastens the end of a posttensioning tendon to the end of a concrete slab.

Anchor bolt
A bolt embedded in concrete for the purpose of fastening a building frame to a concrete or masonry foundation.


Angle
A structural section of steel or aluminum whose profile resembles the letter L.

Annealed
Cooled under controlled condition to minimize internal stresses.

Annular ring nail
Nail with fine rings on the shanks having strong holding power.

Anodizing
An electrolytic process that forms a permanent, protective oxide coating on aluminum, with or without added color.

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ANSI
American National Standards Institute, an organization that forster the establishment of voluntary industrial standards.

Anticlastic
Saddle-shaped, or having curvature in two opposing directions.

Apron
The finish piece that covers the joint between a window stool and the wall finish below.


Arch
A structural device that supports a vertical load by translating it into axial, inclined forces at its supports.

Architect
A person qualified and licensed to design and oversee construction of a building.

Architectural sheet metal roofing
A roof covering made up of sheets of metal in a traditional shop-fabricated pattern such as standing seam, flat seam, or batten seam.

Arc welding
A process of joining two pieces of metal by melting them together at their interface with a continuous electric spark and adding a controlled additional amount of molten metal from a metallic electrode.


Area divider
A curb used to partition a large roof membrane into smaller area, to allow expansion and contraction in the deck and membrane.

Ash dump
A door in the underfire of a fireplace that permits ashes from the fire to be swept into a chamber beneath, from which they may be removed at a later time.

Ashlar
Squared stonework.


Asphalt
A tarry brown or black mixture of hydrocarbons.

Asphalt roll roofing
A continuous sheet of the same roofing materiel used in asphalt shingles.

Asphalt-saturated felt
A moisture-resistant sheet material, available in several different thicknesses, usually consisting of a heavy paper that has been impregnated with asphalt.

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Asphalt shingles
A roofing unit composed of a heavy organic or inorganic felt saturated with asphalt and faced with mineral granular.

ASTM
American Society for Testing and Material, an organization that promulgates standard methods of testing the performance of building material components.

Atactic polypropylene
An amorphous form of polypropylene used as a modifier in modified-bitumen roofing.

Attic
Livable space between the ceiling and roof of a building.



Auger
A helical tool for creating cylindrical holes.

Autoclaved cellular concrete (ACC)
Concrete formulated so as to contain a large percentage of gas bubbles as a result of a chemical reaction that takes place in an atmosphere of steam.

Awning windows
A window that pivots on an axis at or near the top edge of the sash and project toward the outdoors.


Axial
In a directional parallel to the long axis of a structural member.

Axonometric
Pictorial drawing in which the axes vary depending upon the type. Three types are isometric (most common), dimetric, and trimetric.


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