Architectural and Engineering Glossary


Air Slaking

Absorption by quicklime or cement of moisture and carbon dioxide from the atmosphere,causing the material to change its chemical composition.

Air Space

The space above private property or public property for which air rights may be granted.

Air Tap

Same as air vent.

Air Terminal

In a lightning protection system,the combination of a metal rod and its brace or footing,on the upper part of a structure.

Air Terminal Unit

In air-conditioning,same as terminal unit.

Air Test

A test that applies uniform air pressure throughout a drainage system being tested for leakage.This test is recommended in lieu of a water test when there is a danger of water freezing during the test.

Air Tight

Said of an enclosure or barrier that does not permit the passage of air.

Air To Air Resistance

The resistance provided by the wall of a building to the flow of heat.See thermal conductance and thermal resistance.

Air Valve

A valve used to admit or discharge air from a pipeline.

Air Vent

In a water distribution system,a vent for releasing trapped air;usually located at the highest point in the system.

Air Ventilation

The quantity of air which must be supplied to maintain the desired quality of air within a space.

Air Void

A space which is filled with air in cement paste,mortar,or concrete.Also see entrapped air,entrained air.

Air Washer

A water spray system or device for cleaning,humidifying,or dehumidifying the air. 

Air Well

See air shaft.

Air-blown Mortar

Same as shotcrete.


Said of a pipe or apparatus in which the presence of a pocket of air prevents or reduces the desired liquid flow in the pipe or apparatus.Also see air lock,2.

Air-conditioning Unit

Same as room air conditioner.


To vulcanize at ordinary room temperatures,or without the aid of heat.

Air-entraining Agent

An addition for hydraulic cement or an admixture for concrete or mortar which causes air to be incorporated in the form of minute bubbles in the concrete or mortar during mixing,usually to increase its workability and frost resistance.

Air-fuel Ratio

The ratio of the volume (or weight) of air being furnished for combustion to the volume (or weight) of the fuel.

Air-handling Luminaire

Same as air-light troffer.

Air-handling System

An air-conditioning system in which an air-handling unit provides part of the treatment of the air.

Air-inflated Structure

Same as pneumatic structure.

Air-light Troffer

In an air-conditioning system,a unit which combines the functions of a light fixture and an air terminal unit.

Air-lock Strip

The weather stripping which is fastened to the edges of each wing of a revolving door. 

Air-mixing Plenum

In an air-conditioning system,an enclosed volume in which recirculated air is mixed with fresh air for distribution throughout the system.


In the placement of shotcrete,a perforated manifold through which air is introduced into the flow of material.

Air-seasoned Lumber

See air-dried lumber.


To allow material to harden under normal atmospheric pressure and temperature.


Said of a surface that is wetted by the exposure to moisture in air.

Air-supported Structure

See pneumatic structure.

Air-water Jet

1.A jet of air and water mixed,which leaves a nozzle at high velocity;used in cleaning the surfaces of concrete or rock.2.In cleaning concrete or rock surfaces,a high-velocity jet consisting of a mixture of air and water.

Air-water Storage Tank

A water storage tank in which the air,above the water,is compressed. 

Airborne Sound

Sound that reaches a point in a building by propagation from the source through air.


A small tool used for the fine spray application of paint,dye,watercolor pigment,or ink by compressed air.

Airflow Vane

Same as turning vane.

Airfoil Vane

Same as turning vane.

Airplane Bungalow

A Craftsman style bungalow having a gable whose face is parallel to the main ridge of the roof;its second floor is a single room.


A passage for ventilation between thermal insulation and roof boards.


Abbr.for “American Institute of Steel Construction.”


Abbr.for “American Iron and Steel Institute.”


1.A longitudinal passage between sections of seats in an auditorium or church.2.In a church,the space flanking and parallel to the nave;usually separated from it by columns,intended primarily for circulation but sometimes containing seats.

Aisle Access Way

A continuous,unobstructed accessible route around seating,furniture,or desks so as to provide adequate clearance for the disabled.


A passage or walkway within a factory,storage building,or shop permitting the flow of inside traffic.Also see aisle.


Abbr.for “American Institute of Timber Construction.”


A reception hall in an ancient Parthian building.


In southern Spain,an ornament in brick walls,formed of patterns,a half brick deep,more or less complicated.


On drawings,abbr.for aluminum.


1.An alcove or small room opening off the atrium of an ancient Roman house.2.A small room on each side of a cella.


Fine-grained,translucent variety of very pure gypsum,generally white or delicately shaded.