Architectural and Engineering Glossary

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Infrasound

Acoustic oscillations having a frequency below the low-frequency limit (approxi- mately 16 Hz) of audible sound.

Infrastructure

The basic equipment of a building that is necessary for the building to serve its intended function.

Ingle

A fireplace;a hearth.

Inglenook

A fireplace hearth in a corner of a room;often provided with seating;same as chimney corner.

Ingot

A mass of molten metal which has been poured into a mold to solidify;it differs from a casting in that it requires rolling or forging to become a finished or semifinished product.

Ingot Iron

Same as mild steel.

Ingrown Bark, Inbark

See bark pocket.

Inhibiting Pigment

A pigment (such as lead and zinc chromate,zinc oxide,red lead,zinc metal,and barium metaborate) added to paint to inhibit or prevent rust and corrosion of metals or the formation of mildew.

Inhibitor

A substance added to paint to retard drying,skinning,mildew growth,etc.Also see corrosion inhibitor,inhibiting pigment,drying inhibitor.

Initial Backfill

The material used in filling a trench from the top of the bedding to a specified height above a pipe which is laid in the trench.
 

Initial Drying Shrinkage

The difference between the initial length of a moist concrete specimen and the length of the specimen after it is first dried and has reached a stable length;usually expressed as a percentage of the initial moist length.

Initial Grade

Same as natural grade.

Initial Prestress

The prestressing stress (or force) applied to prestressed concrete at the time of stressing.
 

Initial Rate Of Absorption

See absorption rate. 

Initial Set

1.A degree of stiffening of a mixture of cement (or concrete or mortar) and water less than final set;generally stated as the time required for cement paste to stiffen sufficiently to resist the penetration of a weighted test needle.2.Of a mastic compound,adhesive, or coating,the stage in curing or drying when the surface has become sufficiently firm to be unmarked when touched with the finger.
 

Initial Setting Time

The time required for a freshly mixed cement paste,mortar,or concrete to achieve initial set.

Initial Shrinkage

The drying shrinkage that takes place during the setting of a cement,concrete,paste,mortar or the like;caused by the evaporation of moisture.

Initial Stress

Stress in a prestressed concrete member before any loss of stress occurs.
 

Injection Burner

A gas burner that employs a gas jet to thrust air for combustion into the burner and mix it with the gas.

Injection Molding

A molding procedure whereby a heat-softened plastic material is forced from a cylinder into a relatively cool cavity which gives the article the desired shape.

Inlaid Parquet

Inlaid wood flooring,often arranged in simple geometric or decorative patterns.

Inlay, Intarsia, Marquetry

1.A shaped piece of one material embedded in another as part of a surface ornamentation.2.Such ornamentation as a whole.Also see encaustic tile.

Inn

1.A place which provides eating and drinking,but no lodging,for the public;a tavern.2.A hotel.3.A student hostel or residence.4.A hospice.

Inner Bailey

A courtyard within the central defenses of a castle.

Inner Bead

Same as inside stop.

Inner Casing

See inside casing.

Inner Court

1.An open,unoccupied space surrounded on all sides by the exterior walls of a building or structure.2.An open,unoccupied space surrounded by the exterior walls of a building and an interior lot line of the same premises.

Inner Hearth

That part of a hearth contained within a fireplace;the back hearth.

Inner Sanctum

A most sacred place.

Inorganic Material

A material which is composed of minerals,or made from minerals;not animal or vegetable in origin.

Inorganic Silt

See silt.

Inosculating Column

Same as clustered column.

Inpaint

To renew damaged areas on paintings or painted surfaces by repainting.

INR

Abbr.for impact noise rating. 

Inrush Current

See lamp inrush current. 

INS

On drawings,abbr.for “insulate.”

Insanitary

Injurious to health or contrary to sanitary principles.

Inscription

Lettering,often monumental,decorating architecture inside or out.

Insect Screen,window Screen

A very light woven wire used to prevent insects from flying through open windows or doors.

Insect Wire Screening

A woven wire screening having a mesh small enough to provide protection against insects.

Insert

1.A nonstructural repair to correct an appearance defect in laminated timber.2.An inlay of wood veneer,a patch,or a plug used to fill holes in plywood.3.See patch, 2.

Insert Card Reader

A device for providing access to a locked door.The cardholder must insert a card (usually having a magnetic strip) into the device to unlock the door.

Inserted Column

A column which is partially inserted in a wall;an engaged column.

Inserted Grille

A grille that is fabricated separately for mounting in a prepared opening in a door.

Inserted Tenon

See false tenon.

Inset Dormer

A dormer that is partially set belowa sloping roof,unlike the usual dormer that projects entirely abovethe sloping roof.

Inset Porch

Same as integral porch.

Inside Caliper

A type of caliper which is especially designed for measuring the inside diameter of a cylinder or the distance between shapes.

Inside Casing,interior Casing

The inside trim around the interior of a door or window frame.
 

Inside Chimney

Same as interior chimney.