Architectural and Engineering Glossary


Lateral Load

1.See wind load.2.See earth quake load.

Lateral Pressure

The pressure,acting in the lateral direction,exerted by the retained soil against a structure.

Lateral Reinforcement

That part of the steel reinforcement for a reinforced concrete column in the form of transverse hoops,links,or helixes around the vertical reinforcing steel rods.

Lateral Restraint

The restraint that limits lateral movement of the compression flange of a beam.

Lateral Scroll

A fitting which curves in a horizontal plane and is used to terminate a stair handrail.

Lateral Sewer

A sewer which discharges into a branch or other sewer and has no other common sewer tributary to it.

Lateral Support

The bracing for a wall,beam,or structural member,either horizontal (by roof or floor constructions) or vertical (by pilasters,columns,or cross walls).

Lateral-torsional Buckling

See lateral buckling.


Built of brick.

Lateritum Opus

Brickwork of the ancient Romans.

Latest Event Occurrence Time

In CPM terminology,the deadline by which time an event must be completed if the project is not to be delayed.

Latest Finish Date

In CPM terminology,the latest point in time by which no further work must be done on an activity if the project is not to be delayed.

Latest Start Date

In CPM terminology,the latest possible point in time by which an activity must be started if the project is not to be delayed.


See summerwood.


An emulsion of finely dispersed particles of natural or synthetic rubber or plastic materials in water.

Latex Foam Sponge Rubber

made from latex.

Latex Mortar

An admixture used as an ingredient in a batch of mortar-mix to retard its setting.

Latex Paint

A paint containing latex in a water suspension (i.e.,natural or synthetic rubber or plastic particles suspended in water) combined with pigments and other additives acting as binders.

Latex Patching Compound

A compound which consists of a latex (usually styrene butadiene rubber),portland cement,and an aggregate;moisture mildew and alkali resistant;used for patching or leveling a floor.

Latex Sealant

A compound of latex which cures primarily through water evaporation.


A building material used as a base for the application of plaster;see expanded metal lath,gypsum lath,metal lath,split lath,wood lath.

Lath Brick

A longnarrow brick.

Lath Hammer, Lathing Hammer, Lathing Hatchet

A hammer which has a small hatchet blade on the side opposite the hammer head;the blade has a small lateral nick for pulling out nails;esp.used for cutting and nailing wood lath.

Lath Laid-and-set

In plastering,a method of finishing the ceilings and partitions of houses with two-coat work,in which the first coat is called laying,and is often scratched with a broom.

Lath Scratcher

A tool,made from pieces of wood lath, for scratching and roughening base- coat plaster to improve the bond of the next coat.


A machine for shaping circular pieces of wood,metal,etc.,by rotating the material about a horizontal axis while a stationary tool cuts away the excess material.


A structure made of laths or slats to shelter growing plants requiring shade and wind protection.


1.A quantity of laths.2.The erecting or placing of laths.

Lathing Board

See backup strip.


In Spanish Colonial architecture,one of a number of light,relatively straight saplings, usually about 3 feet (1 m) long,that has been stripped of its bark and laid across log beams (vigas) of a structure,either diagonally so as to create a herringbone ceiling pattern or laid at right angles to the vigas.A matting of reeds,placed over the latias,is then covered with a layer of tamped earth,dried mud,or adobe mixed with grass,to serve as a roof.

Latia Labrada

A latia that has been split along its length;usually laid across vigas with its flat side down.

Latin Cross

A cross with the vertical bar substantially longer than the horizontal bar.


1.The perpendicular distance in a horizontal plane of a point from an east-west axis of reference.2.In surveying, the north-south component of a traverse course.


An ancient Roman term for a bath or place to wash,or a water closet in a private home.


1.A public toilet.2.A privy.


A stove or heater set under a mantel piece,heating the room by direct radiation and one or more rooms above by hot air.


An alloy of copper and zinc;yellow in color,resembling brass.


See ladkin.


1.A network,often diagonal,of strips,rods,bars,laths,or straps of metal or wood,used as screening or for airy,ornamental constructions.2.A regular member triangularly braced,e.g.,a lattice girder,a lattice truss.

Lattice Beam

See lattice girder.

Lattice Boom

A boom of lattice-type construction,usually fabricated of steel angles or tubing.

Lattice Girder,lattice Beam

An open girder in which the web consists of diagonal pieces arranged like latticework.

Lattice Molding

A wood molding,rectangular in section and broad in relation to its projection,resembling the wood strips used in latticework.

Lattice Porch

A porch enclosed by a lattice,usually of wood strips; provides limited privacy,yet permits breezes to flow through the porch.

Lattice Truss

A truss consisting of upper and lower horizontal chords,connected by web members which cross each other;usually stiff ened by joining at the intersections of the braces.

Lattice Window

A window casement,fixed or hinged,with glazing bars set diagonally.


Reticulated or net-like work formed by the crossing of laths or narrow,thin strips of wood or iron,usually in a diagonal pattern.


See Philippine mahogany.

Laundry Chute, Clothes Chute

A shaft for conveying soiled clothing,bed linen,etc.,by gravity from an upper to a lower floor of a building.

Laundry Room

A room equipped with one or more washing machines,washtubs,driers,ironing boards,etc.for household linen and/or personal effects.