Construction Dictionary: A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z Term Definition L Cut A piece of tile cut or shaped like the letter L. L'Enfant Plan of Washington, DC Adopted plan for the Capital in 1771. Daniel Burnham later worked on additions and adaptations of the plan. L-Mold A metal molding strip with an L-like section, used to edge plaster or gypsum wallboard. Labor and Material Bond A bond, secured by the general contractor, which guarantees that the costs for labor and materials for the project will be paid. Labor Union A trade union. Laboratory A room or building equipped for physical or chemical testing, experimentation, or analysis. Laboratory Cabinet A case, box, or piece of furniture with sets of drawers or shelves, with doors, primarily used for storage, used in a place or area for scientific studies or commercial and institutional laboratories and testing facilities. Laboratory Counter A level surface in a laboratory where equipment is placed and kept and where work may be performed. Laboratory Equipment Devices and tools used in laboratory work. Laboratory Hot Plate A heating device in a laboratory. Laboratory Incinerator A device in a laboratory in which waste materials are burned. Laboratory Incubator An apparatus used in a laboratory for the maintenance of controlled conditions. Laboratory Table A surface on which laboratory materials and devices are kept and used. Lac A natural resin secreted by certain insects which live on the sap of trees in India and other Oriental countries; marketed in various forms, such as seed lac, button lac, and shellac. lace Very light open-work fabric made from cotton, viscose or nylon; pattern can be applied to mesh ground. It is used in windows for privacy, as bed drapes and as romantic-style bedcovers, cushion covers and dressing-table skirts. It is also available as edgi Laches Undue delay in asserting one's legal rights, resulting in loss of the rights. Lacquer A sometimes colored liquid made of shellac dissolved in alcohol, or of synthetic substances, that dries to form a hard protective coating. Lacunar A ceiling made up of vaults or recessed panels. Lacunaria A recessed panel in a ceiling. Ladder A frame consisting of two parallel side pieces connected by rungs at suitable distances to form steps on which persons may climb up or down. Ladder The strings on a blind used to support the slats. Ladder Bar A prefabricated reinforcement designed for embedment in the horizontal mortar joints of masonry; parallel deformed side rods connected in a single plane, by cross wires, thus forming a ladder-like design. Ladder Cage A cage-like structure surrounding a wall-mounted ladder for safety. Ladder Rung A horizontal round member used as a step on a ladder. Ladder Step A horizontal flat member used as a step on a ladder. Ladder, Pool See Pool Ladder. Lag Delay in response. Lag Rod A large diameter rod with a square or hexagonal head. Lag Screw A large diameter wood screw with a square or hexagonal head. Laid Off See Double-Up. Laid-On See Double-Up. Laitance A layer of weak and nondurable material containing cement and fines from aggregates, brought by bleeding water to the top of overwet concrete, the amount of which is generally increased by overworking or overmanipulating concrete at the surface by imprope Lake Asphalt See Natural Asphalt. Lake Pigment Pigment made by putting an organic dye on a base of fine particles of inert or translucent pigment. Lake Sand Sand consisting predominantly of fine, rounded particles. Lally Column Tradename; a hollow steel column, sometimes filled with concrete. lambrequin Stiff, shaped pelmet inspired by the elaborate harnesses of horses. They were first used in 17th century French interiors often in conjunction with portires. As they developed over the centuries, they frequently continued down the sides of the frame to fo Lamella A unit of a surface network of closely spaced uniform ribs or beams, usually arranged in two or three intersecting diagonal lines; curved vaults and domes have been built of wood, steel, and concrete lamellas. Lamina The layers of material in a laminate. Laminar Scale Rust formation in heavy layers. Laminate 1. To form a product by bonding together two or more layers of materials. 2. The product so formed, such as a plastic laminate. laminate A thin protective covering, bonded to a material. Laminate, Paper-Base A multilayer panel made by compressing sheets of resin-impregnated paper together into a solid mass. Laminated Glass A glazing material consisting of outer layers of glass laminated to, and encasing, an inner layer of transparent plastic; used for automobile windshields and bulletproof glass. Laminated Plastic See Plastic Laminate. Laminated Rubber Several layers of rubber bonded together with adhesive under pressure. Laminated shingles Shingles that have added dimensionality because of extra layers or tabs, giving a shake-like appearance. May also be called "architectural shingles" or "three-dimensional shingles." Laminated Timber An assembly made by bonding layers of veneer or lumber with an adhesive so that the grain of all laminations is essentially parallel. Laminated Wallboard Two or more layers of gypsum board held together with an adhesive. Laminated Wood A product made by bonding layers of veneer or lumber with an adhesive so that the grain of all layers is generally parallel. Laminating Bonding together two or more layers of materials. Laminating Compound A cementitious material, usually regular joint compound, used to adhere two or more layers of gypsumboard together. Lamp, Incandescent See Incandescent Lamp Lamp, Steri See Steri Lamp. Lampback Pigment made by burning coal tar distillates without sufficient air; not quite true black. Lampholder A device to support an electric lamp mechanically and connect it electrically to the circuit conductors. Lanai Porch, veranda, or covered patio. Land 1. The surface of the earth and all its natural resources. 2. A portion of the earth's solid surface defined by boundaries or ownership; privately or publicly owned. 3. See Root Face. Land Contract A contract for sale of land where title does not pass to the purchaser until all, or a certain number, of the payments have been made; also called Contract of Sale. Land Plaster Coarsely ground natural gypsum used agriculturally as a soil conditioner. Land Residual A real estate appraisal technique where a reasonable return on the improvements is first deducted from the income, the balance being attributable to the land. Land Surveyor A person who surveys land. Land Title Porous clay pipe with open butt joints. Landing A platform between flights of stairs or at the termination of a flight of stairs. Landing A platform between flights of stairs or at the termination of a flight of stairs. Often used when stairs change direction. Normally no less than 3 ft. X 3 ft. square. Landing Terrazzo A staircase landing with terrazzo tile mounted on its surface. Landlord The owner of property that is rented to a tenant. Landscape 1. Natural scenery. 2. To improve a site by modification of the terrain, the planting of trees, shrubs, and ground cover, and the addition of hardscape. Landscape Architect One whose profession is designing the arrangement of land for human use involving vehicular and pedestrian ways and the planting of groundcover, plants, and trees. Landscape Timber Large, treated lengths of lumber used to decorate and act as soil erosion barriers and retaining wall members. Lane Joint Cracks Longitudinal separations along the seam between two paving lanes caused by a weak seam between adjoining spreads in the courses of the pavement. Langly A measure of solar radiation, equal to 1 calorie per square centimeter. Lantern A raised structure on a roof, glazed to admit light. Lap 1. The overlap of two roofing plies. 2. The length by which one bar or sheet of fabric reinforcement overlaps another. 3. The length of the overlap of two reinforcing bars; also called Lap Splice. 4. The amount of extension of one brick or any other mason Lap To cover the surface of one shingle or roll with another. Lap joint A joint made by placing one member partly over another and bonding the overlapped portions. Lap Siding See Bevel Siding. Lap Splice See Lap, 3. Lapped Joint In wallpapering, a joint made by trimming one selvedge and overlapping the other. Lapping Smoothing a metal surface to high degree of refinement or accuracy using a fine abrasive. Large Calorie See Calorie, 2. Laser 1. A device that generates an intense beam of coherent monochromatic radiation in the infrared, visible, or ultraviolet region of the electromagnetic spectrum, by stimulated emission photons from an excited source; used in communications, industry, and me Latch 1.A bar with a catch and lever used as a fastening for a gate. 2. A spring-lock requiring a key to pass from the outside. Latch A beveled metal tongue operated by a spring-loaded knob or lever. The tongue's bevel lets you close the door and engage the locking mechanism, if any, without using a key. Contrasts with dead bolt. Latch Set A fastening assembly for a door or window, operable from both sides, and lockable with a key. Latent Ambiguity A term of a contract that appears on its face to be unambiguous, but that is made ambiguous by external circumstances. Latent Defect A construction defect that is not perceptible by ordinary observation. Latent Heat Heat that changes the state of material from a solid to a liquid or a liquid to a gas. Latent Heat Gain The addition of heat to an enclosure by an increase in moisture content. Latent Heat of Condensation Amount of heat lost by a pound of a substance to change its state from a gas to a liquid. Latent Heat of Vaporization Amount of heat required per pound of a substance to change its state from a liquid to a gas. Lateral 1. Relating to the side. 2. At right angles to the long direction of the member; crosswise; transverse. Lateral (electric, gas, telephone, sewer and water) The underground trench and related services (i.e., electric, gas, telephone, sewer and water lines) that will be buried within the trench. Lateral Brace A temporary or permanent structural brace to resist lateral movement of a truss or beam. Lateral Branch See Horizontal Branch. Lateral Force A force acting generally in a horizontal direction, such as wind, earthquake, or soil pressure against a foundation wall. Lateral Force Coefficients Factors applied to the weight of a structure or its parts to determine lateral force for a seismic design. Lateral Load 1. The horizontal component of the load produced by an arch, dome, vault, or rigid frame. 2. A horizontal load applied to a structure or member such as wind or earthquake. Lateral Pressure Horizontal pressure such as the force of soil against the side of a high foundation wall. Lateral Slip Fault A fault whose relative displacement is purely horizontal. Lateral Support A force or structural member that prevents a structure or earthen mass from moving in a lateral or horizontal direction. Lateral Thrust 1. The pressure that any load or force exerts sideways or through the ends of the members. 2. The horizontal component of the force or thrust produced by an arch, dome, vault, or rigid frame. Lateral-Force-Resisting System The portion of the structure composed of members designed to resist forces related to earthquake, wind, or other lateral effects. Latewood The portion of the annual growth ring that is formed after the earlywood formation has ceased; it is usually denser and stronger mechanically than earlywood; also called Summerwood. Latex A water based emulsion of a synthetic rubber or plastic obtained by polymerization and used commonly in coatings and adhesives. Latex Paint A water-based paint that can be thinned and washed from applicators with water. Latex-Portland Cement Grout A portland cement grout with a special latex additive which results in a less rigid, less permeable grout than regular portland cement grout. Latex-Portland Cement Mortar A mixture of portland cement, sand, and special latex additives which is used for bonding tile to back-up material. Lath A building material of narrow wood, metal, gypsum, or insulating board that is fastened to the frame of a building to act as a base for plaster, shingles, or tiles. Lath A building material of wood, metal, gypsum, or insulating board that is fastened to the frame of a building to act as a plaster base. Lath A wood strip, metal mesh, or gypsum board which acts as a backing and/or reinforcing agent for the plaster scratch coat or initial mortar coat; a plaster base. Lath and Plaster Membrane 1. A thin slab of lath and plaster including any integral supporting and stiffening members. 2. Lath and plaster as a unit of structure. Lath, Expanded Metal See Expanded Metal Lath. Lath, Stucco See Stucco Lath. Lathe Tool A blacksmith's tool used to handle hot metals. Lathe, Shop See Shop Lathe. Lattice A framework of crossed wood or metal strips. Lattice An open framework of criss-crossed wood or metal strips that form regular, patterned spaces. Lattice Molding Flat strip molding used in the construction of lattices. Lattice Truss A steel truss where the top and bottom chords are connected together by a steel lattice. Lauan A variety of Philippine mahogany, of moderate strength and durability, with wood of light yellow to reddish brown or brown. Lauan Door A door made of Philippine mahogany veneer. Lauan Veneer Very thin sheets of Philippine Mahogany, which may be combined with glue to create plywood or glued onto another surface to create a finished surface. Launching Process where stone stockpiled along top bank is undercut and slides down slope thus protecting the bank against future erosion. Laundry A room for washing and drying of clothes and linens. Laundry Chute A chute that leads from an upper floor to a lower floor by which soiled laundry is conveyed. Laundry Equipment Appliances and materials used for cleaning clothes. Laundry Tray A tub with hot and cold water supply and a drain, used in a laundry room. Lav Lavatory. Lavatory 1. A basin with drainage and running water primarily used for washing the face and hands. 2. A room with a toilet and wash basin. Lavatory Carrier A horizontal structure attached to a bathroom wall to support and mount a lavatory. Lavatory Faucet A water dispensing device in a bathroom sink or lavatory. Law A rule of conduct enforced by courts. Lawn An area of ground covered with mown grass. Lawn Irrigation The supply of water to grassy areas by artificial means. Lawsuit A proceeding in which the jurisdiction of a court is invoked to resolve to a dispute between two or more parties. Lawyer A person who is educated in and authorized to practice law. Lay Out The measuring and setting out of work according to the design drawings. Layer A stratum of weld metal consisting of one or more weld beads. Laying Overhand Laying brick on the farther face of a wall from a scaffold. Layout A full-sized drawing showing arrangement and structural features. Layout Stick A long strip of wood marked at the appropriate joint intervals for the tile to be used; used to check the length, width, or height of the tilework; also called Idiot Stick. Lazy Susan 1. A revolving circular arrangement of shelves. 2. A circular revolving cabinet shelf used in corner kitchen cabinet unit. Lb Symbol for pound or pounds. Leaching Field A land area containing a series of subterranean perforated pipes that allow septic tank effluent to percolate into the soil; also called Disposal Field. Leaching Pit An excavated hole in the ground that can hold solids but allows liquids to pass through and leach into the ground. Lead 1. A heavy soft malleable ductile plastic but inelastic bluish white metallic element found mostly in combination, used in pipes, cable sheaths, batteries, solder, roofing, flashing, and shields against radioactivity. 2. A section of a wall built at the c Lead Carbonate, Basic See Basic Lead Carbonate. Lead Drier Almost water-white drier which works on body of paint film; various combinations of lead, cobalt, and other driers are used in formulating many modern finishes. Lead glass A glass of high refractive index containing lead oxide. Lead Lined Wallboard Gypsum wallboard with a ply of lead sheeting to be used in providing radiation protection in x-ray facilities. Lead Oxide Compound in several combinations of lead and oxygen, e.g., litharge and red lead. Lead Sulphate, Basic See Basic Lead Sulphate. Lead Wool A mass of lead shavings used primarily for packing or caulking. Leaded Glass A stained glass window, with the pieces of glass, often of irregular size and shape, set in a lead framework. Leaded Zinc Basic lead sulphate united with zinc oxide. Leaded Zinc Oxide White pigment made by combining lead sulphate and zinc oxide. Leader See Downspout. leading edges Inner vertical edges of a pair of curtains or draperies. Leadless Glaze A ceramic coating matured to a glassy state on a formed article, or the material or the mixture from which the coating is made, to which no lead has been deliberately added; does not imply that the glaze is nontoxic or that it contains no lead; because of Leaf 1. The hinged or sliding part of a shutter, door, or gate. 2. One of a pair of doors. Leafing The overlapping arrangement of aluminum or gold bronze powders in a paint, similar to that of fallen leaves; good leafing is important in producing a metallic appearance and is caused by using treated or coated pigments along with suitable bronzing liquid Leak Detector 1. Device or instrument such as halide torch, an electronic sniffer, or soap solution used to detect leaks. 2. Device used to detect and locate refrigerant leaks. Leakage 1. Entrance or escapage through a crack or hole, usually by a fault or mistake. 2. The loss of electricity through faulty insulation. Lean Concrete A concrete mix that is low in water and cement content, usually used as a stable base or fill. Lean Mixture Any plaster mortar containing a relatively high ratio of aggregate to cementitious material; a mortar mix that is too lean and has poor working qualities is said to be harsh. Lean Mortar Mortar containing a low percentage of cementitious components, not workable; see Harsh Mortar. Lean-To A shed on the side of a building with a sloping roof in a single plane. Leaning Edge In gypsumboard, a factory edge formed out of square with the surface. Lease An agreement whereby a tenant (lessee) obtains use of equipment, facilities, or real property for a specified period of time from the owner (lessor) usually by payment of a specified rent and under specified conditions. Leaseback A financial arrangement in which a tenant agrees to lease real property for a period during which the lease consideration will cover all mortgage payments and the lessor will own the property free and clear at the end of the lease term. Lectern A desk-like stand for holding a book or papers for a lecturer. LED Light-Emitting Diode. Ledger A wood or metal member bolted to a masonry wall to carry floor joists, ceiling joists, or rafters. Ledger (for a Structural Floor) The wooden perimeter frame lumber member that bolts onto the face of a foundation wall and supports the wood structural floor. Ledger Bolt A bolt set into a masonry wall to secure a wood or metal ledger. Ledger strip A strip of lumber nailed along the bottom of the side of a girder on which joists rest. Ledgerboard The support for the second-floor joists of a balloon-frame house. Leech field A method used to treat/dispose of sewage in rural areas not accessible to a municipal sewer system.  Sewage is permitted to be filtered and eventually discharged into a section of the lot called a leech field. Leg 1. A tile wall running alongside a bathtub or abutment. 2. A narrow strip of tile floor. Legal Description 1. The description of a piece of property such that it can be positively identified for purposes such as purchase, sale, hypothecation, title insurance, and locating it on the land. 2. The lot, block, and tract numbers of a recorded subdivision. 3. A mete Length 1. The extent from end to end of an object. 2. The longer or longest of the 2 or 3 dimensions of an object. 3. The dimension measured between the ends of a masonry unit, usually the dimension of the masonry unit which is parallel to the face or length of Length Seam See Side Seam. Leno Weave Weave in which warp yarns, arranged in pairs, are twisted around one another between picks of weft yarn. Lens 1. A transparent glass or plastic substance with one or both sides curved for concentrating or dispersing light rays, as in optical devices. 2. The diffuser of a lighting fixture. Lessee One that holds property under a lease. Lessor One that conveys property by lease. Let-in brace Nominal 1 inch-thick boards applied into notched studs diagonally. Let-in brace Nominal 1 inch-thick boards applied into notched studs diagonally. Also, an "L" shaped, long (@ 10') metal strap that are installed by the framer at the rough stage to give support to an exterior wall or wall corner. Let-In Bracing Diagonal bracing, usually 1" x 4" or 1" x 6", nailed into notches cut in the face of the studs so as to avoid an increase in the thickness of the wall. Letter Box A receptacle for the placement and storage of mail. Letter of Credit A letter written by a bank guaranteeing that drafts up to a certain amount will be honored; in some cases this will serve as a substitute for a surety bond. Letter Sign Sign composed of individual letters, usually of metal or plastic, mounted on a rigid background surface. Letter Slot An opening in a wall or door for the insertion of mail. Level 1. The position of a line or plane when parallel to the surface of still water. 2. A tool of wood, metal, or plastic used in testing for horizontal and vertical surfaces; see Spirit Level. 3. An instrument used in determining differences of elevation; see Level True horizontal. Also a tool used to determine level. Level Area A specified surface that does not have a slope in any direction exceeding 1/4 inch in one foot from the horizontal (2.083 percent gradient). Level Floor To bring a floor in conformance with a specified grade. Level Payment Mortgage A mortgage with identical monthly payments over the life of the loan. Leveler, Dock See Dock Leveler. Leveling In painting, the formation of a smooth film on either a horizontal or vertical surface, independent of the method of application; a film with good leveling characteristics is usually free of brush marks or orange peel effects. Leveling Coat A coat or layer of plaster or stucco which brings the surface to a true level plane. Leveling Plate A steel plate placed in grout on top of a concrete foundation to create a level bearing surface for the lower end of a steel column. Levelling Course See Regulating Course Lever A simple machine consisting of a rigid bar pivoted about a fulcrum (fixed point) which can be acted upon by a force in order to move a load. Lever Handle A horizontal handle for operating the bolt of a lock. Levolor Blind and shade fabricator. Products include Mark I, Riviera, Monaco, Ovation, Cirrus, Nu Wood, Natural Shades, Century Collection, and others. A division of Newell. (4110 Premier Drive, Highpoint, NC 27265) Levolor 1" miniblind 5 gauge contract aluminum miniblind made by Levolor LH 1. Left hand. 2. Left Hand, a door handing designation. LH Joist A type of long-span high strength bar joist. LH Series A standard Steel Joist Institute designation for longspan steel joists. LHR Left Hand Reverse, a door handing designation. Liabilities Creditor claims on the assets of a business. Liability Legal responsibility. Liability Insurance Insurance that will pay damages for which the insured becomes liable. Library A room or building used for the storage and use of books. Licensed Architect An architect duly licensed by the state to practice. Licensed Contractor A contractor duly licensed by the state to construct buildings. Lien A legal clam by a party against another party for satisfaction of a monetary claim. Lien An encumbrance that usually makes real or personal property the security for payment of a debt or discharge of an obligation. Lien Claim A claim to obtain a lien against real property because of nonpayment by the owner for labor, services, or material supplied for a work of improvement. Lien Foreclosure Action 1. A lawsuit to foreclose a Mechanics' Lien. 2. A lawsuit for foreclosures on property brought about to secure payment due to the holder of a lien and judgment against the real property involved. Lien Release Notice A notice showing that the lien amount has been satisfied and releasing the lien claim against the real property involved. Life An estimated time period over which a structure will function if limited only by deterioration of materials. Life Estate The right to own, use, and occupy real property during one's lifetime. Life Expectancy The average time a material, piece of equipment, or assembly would be expected to give satisfactory service under the conditions in which it is used. Life-Cycle Cost A cost that takes into account both the first cost and costs of maintenance, replacement, fuel consumed, monetary inflation, and interest over the life of the object being evaluated. Lifeguard Chair A raised chair, equipped with a ladder, that enables a lifeguard to view a large area. Lift 1. The amount of material placed at one time. 2. A layer of concrete. 3. A layer or course of paving material applied to a base or a previous layer. 4. A device to elevate loads. Lift, Auto See Auto Lift. Lift, Hydraulic See Hydraulic Lift. Lift-Slab Construction A method of building multi-story sitecast concrete buildings by casting all the slabs in a stack on the ground, then lifting them up the columns with jacks and welding them in place. Lifting 1. In painting, the buckling of the finish coat when applied over previous coat which is not yet dry or when solvents in second coat are too strong. 2. Softening of undercoat by solvents used in coats which follow; usually caused by not allowing sufficien Light 1. Daylight. 2. A lamp. 3. An appearance of brightness. 4. A pane of glass in a window. 5. Low in weight, density, or intensity. Light Space in a window sash for a single pane of glass. Also, a pane of glass. Light Duty Pavement Pavement designed for low traffic volumes and light loads. Light Duty Tile Tile suitable for limited pedestrian traffic such as entryways in single family residences. Light Track An electrified U-shaped member attached to a ceiling or wall and acting as a channel for sliding light fixtures. Light Well A court, open to the roof, to provide light and ventilation to rooms that face it. Light, Dental See Dental Light. Light, Pool See Pool Light. Light, Surgical See Surgical Light. Light-Emitting Diode (LED) An electric component that emits light. Lighting An artificial supply of light or the apparatus providing it. Lighting Contractor The person in charge of installing an apparatus which supplies an artificial supply of light. Lighting Fixture An assembly having one or more lampholders, or a lampholder used in lieu of such an assembly. Lighting Outlet An outlet intended for the direct connection of a lampholder, a lighting fixture or a pendant cord terminating in a lampholder. Lighting Standard A pole supporting a lighting fixture as along streets or in a parking lot or athletic field. Lightly Coated Electrode A filler-metal electrode, used in arc welding, consisting of a metal wire with a light coating applied subsequent to the drawing operation, primarily for stabilizing the arc. LightMaster aluminum blinds without rout holes, made by Levolor. Lightning Arrester A device connected to an electrical system to protect from lightning and voltage surges. Lightning Rod A metallic rod mounted on a high part of a structure, attached to a ground wire, to divert lightning into the earth. Lightweight Aggregate 1. Aggregate of low specific gravity, such as expanded or sintered clay, shale, slate, diatomaceous shale, perlite, vermiculite, or slag; natural pumice, scoria, volcanic cinders, tuff, and diatomite, sintered fly ash or industrial cinders; used to produc Lightweight Block A concrete masonry unit constructed of lightweight materials and used to reduce the weight of walls. Lightweight Concrete See Concrete, Lightweight. Lightweight Concrete Firestop Lightweight concrete used as firestop. Lignin An amorphous polymeric substance related to cellulose that together with cellulose forms the woody cell walls of wood and the cementing material between them. Lime 1. Various compounds of calcium oxide and magnesium oxide, obtained by heating forms of calcium carbonate, such as shells or limestone; used in mortar and plaster; also called Caustic Lime and Quicklime. 2. A dry white powder consisting essentially of the Lime Mortar Mortar in which the cementing agent is lime. Lime Plaster Basecoat plaster consisting essentially of lime and an aggregate. Lime Putty Slaked or hydrated lime that is mixed with water to form a putty like mixture. Lime Scale The build-up of calcium carbonate on plumbing fixtures and in piping from the water supply. Limestone A sedimentary carbonate rock, composed chiefly of calcite (CaCO3), but sometimes containing appreciable dolomite. Limestone Aggregate Granular, crushed limestone. Limestone Lintel Limestone member placed within masonry wall or partition to support masonry or other construction over wall or partition opening. Limestone Panel A limestone slab, relatively thin with respect to other dimensions, and rectangular in shape. Limit Control Control used to open or close electrical circuits as temperature or pressure limits are reached. Limit switch A safety control that automatically shuts off a furnace if it gets too hot. Most also control blower cycles. Limited Partnership A partnership in which the management authority and liability of some of the partners is limited to their original investment; there must be at least one general partner who remains fully responsible for business liabilities and who runs the business. Limiting Friction The maximum value friction can have before motion ensues. Line 1. A length of string, thread, or rope. 2. A utility service such as a water pipe, electrical wire, or sewer pipe. 3. To cover the inside surface of an object with some material. 4. A circuit in a communication system. 5. The boundary of an area; a defini Line Pin Metal pin used to attach string line used for alignment of masonry units. Line Wire Taut parallel horizontal wires installed on the outside of wood studs to act as a backing for weatherproof paper under the stucco netting of an exterior stucco wall assembly. Lineal foot A unit of measure for lumber equal to 1 inch thick by 12 inches wide by 12 inches long. Examples: 1" x 12" x 16' = 16 board feet, 2" x 12" x 16' = 32 board feet. Linear Measure Measurement along a line. linen A strong cloth spun from flax. Its disadvantages are a tendency to shrink and crease. It is more practical when blended with cotton to form a linen union, and can also be strengthened with synthetic yarn. It is used for chair and sofa slip-covers and occa Linen Chute An inclined plane, sloping or vertical channel, or passage down or through which soiled linen may pass. linen union An inexpensive and hardwearing linen-and-cotton mixture. Liner Panel A panel used for interior finish. Liner, Flue See Flue Liner. Liner, Pool See Pool Liner. Linerless Pool Prefabricated component pool that retains water without additional waterproofing when assembled. lining A secondary hanging sewn in at the back of a curtain to protect it from the light and improve its hanging qualities. lining fabric A secondary fabric used to back curtains to protect them from light and dust. Usually a cotton sateen fabric with a slight sheen. Lining Paper Wallpaper without a ground (overall background color), used mostly for wall conditioning. Lining, Carpet See Carpet Padding. Link, Beam That part of a beam in an eccentrically braced frame which is designed to yield in shear and/or bending so that buckling of the bracing members is prevented. Linoleum A tough wearing resilient floor covering, commonly in sheet form, consisting of a burlap back coated with a preparation of linseed oil, powdered cork, and pigments. Linoleum and Oilcoat Varnishes Special highly flexible and elastic varnishes. Linoleum Knife See Hook Knife. Linoleum Removal The act or process of scraping away old linoleum flooring, commonly done by a specially designed apparatus which mechanically removes both linoleum and adhesive . Linoleum Varnish Special highly flexible and elastic varnish. Linseed Oil Yellowish drying Oil extracted from flax plant seed, widely used as a vehicle for lead-based paints; it is soluble in ether, benzene, and turpentine; metallic salts or driers are added to increase rate of drying; see also Bodied Linseed Oil and Boiled Lin Lint Strainer A device mounted in the pump influent line to catch lint and other debris. Lintel A horizontal structural member that supports the load over an opening such as a door or window. Lintel A horizontal structural member, usually made of stone, wood or metal, which supports the load over an opening; a Header. Lintel Block A channel block. Lintel Coarse See String Course. Lintel, Limestone See Limestone Lintel. Lintel, Masonry See Masonry Lintel. Lintel, Steel Steel member placed within wall or partition to support loads over an opening. Lip The chain and/or stuffer left on the edge of carpet after it has been cut. Lip Molding A molding with a lip which overlaps the piece against which the back of the molding rests. Lip of a Strike The projecting part of a door lock strike on which the latch bolt rides. Lipping Laying brick so that the top edge of the unit is set in from the plane surface of the wall. Liquefaction Transformation of a granular material, the soil, from a solid state into a liquid state as a consequence of vibrations induced by an earthquake. Liquefied Propane Gas A compressed gas, such as propane or butane, used for fuel. Liquid A substance that flows freely like water and has a form that has a definite volume but no fixed shape; one of the three states of matter; compare with solid and gas. Liquid Absorbent Chemical in liquid form which has the property to take on or absorb other fluids. Liquid Applied Membrane A roofing system applied in one or more coats, suitable for intricate shapes such as cast-in-place concrete structures. Liquid Assets Current assets that are, or can be, readily converted to cash. Liquid Collector A collector with a liquid as the heat transfer fluid. Liquid Driers Solution of driers in paint thinners. Liquid Indicator Device located in liquid line which provides a glass window through which liquid flow may be watched. Liquid Line Tube which carries liquid refrigerant from the condenser or liquid receiver to the refrigerant control mechanism. Liquid Nitrogen Nitrogen in liquid form which is used as a low- temperature refrigerant in expendable or chemical refrigerating systems. Liquid Receiver Cylinder (container) connected to condenser outlet for storage of liquid refrigerant in a system. Liquid Receiver Service Valve Two- or three-way manual valve located at the outlet of the receiver and used for installation and service purposes; also called the King Valve. Liquid Waste The discharge from any fixture or appliance connected to a drainage system which does not receive fecal matter. Liquid Wood Filler Varnishes of low viscosity, usually containing extending pigment, for use as a first coating on open- grain woods; its purpose is to afford a non-absorbent surface for succeeding coats of varnish; it is frequently colored so as to stain and fill in one op Liquid-Vapor Valve Refrigerant Cylinder Dual hand valve on refrigerant cylinders which is used to release either gas or liquid refrigerant from the cylinder. Liquidate Wind up the affairs of a firm by ascertaining liabilities and apportioning assets; to determine by agreement or by litigation the precise amount of indebtedness, damages, or accounts. Liquidated Damages An amount determined by contract in advance of injury to be paid to compensate a party for an injury or damages. Liquidity Availability of cash, cash equivalents, and readily sold assets. Liquor Solution used in absorption refrigeration. Lis Pendens A document recorded in the county recorder's office that gives public notice of litigation involving title to or the possession of real property or real estate. List Price A published price, subject to possible trade discounts. Listed Listed means equipment or materials included in a list published by a listing agency that maintains periodic inspection on current production of listed equipment or materials and whose listing states either that the equipment or material complies with app Listing Electrical materials, devices, fixtures, fittings, equipment, appliances and accessories that are shown in a list published by the enforcing agency, or by an approved testing agency, qualified and equipped for experimental testing and maintaining adequate Listing Agency Listing agency means an agency accepted by the Administrative Authority which is in the business of listing or labeling and which maintains a periodic inspection program on current production of listed models, and which makes available a published report Listing Mark An independent laboratory mark or manifest indicating the material bearing this mark may be used in test certified by that lab. Liter A unit of volume equal to 1000 cubic centimeters, 1000 cubic centiliters, or 1.057 quarts. Litmus A dye that turns red in acidic conditions and blue in alkaline conditions; litmus paper is stained with litmus to be used as a test for acids or alkalis. Littoral Of or pertaining to a shore, especially of the sea. Littoral Drift The sedimentary material moved in the littoral zone under the influence of waves and currents. Littoral Material See Littoral Drift. Littoral transport The movement of littoral drift along the shoreline by waves and currents. Includes movement parallel (longshore transport) and perpindicular (on-offshore transport) to the shore. Live Load Any load that is not permanently applied to a structure; the weight of people, furnishings, machines, and goods in or on a building; the vertical load superimposed by the use and occupancy of a building; all loads on a building except dead and lateral loa Live Part Live parts are those parts which are electrically connected to points of potential different from that of the earth. Live Space A space with reflective surfaces so that sound can be sustained through several reflections. Live Wire The hot wire, carrying electric current, as opposed to the neutral or ground. Livering Formation of curds or gelling; coagulation of varnish finishing material into a viscous, rubber-like mass; usually caused by chemical reaction of two or more non-mixing products. Living Room A room in a residence for the occupants' common social pursuits. Living Standard Standard of living. Living Unit A house or apartment for the use of one family. Load 1. A force that is applied to a body. 2. A weight or force acting on a structure. 3. Applied external force, such as gravity and wind. 3. Any device that consumes electrical power, such as a motor, lamp, or toaster; the load on an electrical circuit. Load Bearing Supporting a superimposed weight or force. Load Bearing Metal Stud Vertical load bearing, formed "C" channel of steel, component within framed wall, able to withstand structural loads imposed by wind loads, building loads, movement and deflection of structure. Load Bearing Stud A wooden stud which supports an imposed load in addition to its own weight. Load Bearing Wall A wall designed and built to carry superimposed vertical and shear loads as opposed to non-load-bearing walls which carry only their own weight. Load bearing wall Includes all exterior walls and any interior wall that is aligned above a support beam or girder. Normally, any wall that has a double horizontal top plate. Load Duration The period of continuous application of a given load, or the sum of the periods of intermittent application of the same load. Load Factor 1. The percentage of the connected load which is likely to occur at any time. 2.The percentage of the total connected fixture-unit flow rate which is likely to occur at any point in the drainage system. 3. The percentage of the total electrical load which Load, Factored The load, multiplied by appropriate load factors, used to proportion structural members by the strength design method. Load, Service See Service Load. Load-Bearing Partition A vertical structural interior wall supporting an integral part of the construction above. Loader An excavating machine with a movable bucket or scoop, used to transport earth, crushed stone, or other construction materials. Loading Dock A raised platform adjacent to a loading door so that trucks may be loaded or unloaded with the truck bed at the same level as the warehouse floor. Loading Dock Equipment Powered or hand operated machinery to help load and unload freight. Loading Pump A hand pump for filling bulk materials into application tools. Loam A soft, easily worked soil containing sand, silt and clay. Loan Money lent at interest. Loan The amount to be borrowed. Loan Fee A fee for negotiating a loan, in addition to the interest. Loan to value ratio The ratio of the loan amount to the property valuation and expressed as a percentage. E.g. if a borrower is seeking a loan of $200,000 on a property worth $400,000 it has a 50% loan to value rate. If the loan were $300,000, the LTV would be 75%. The highe Lobby An entrance room or anteroom. Local Access Streets Most of the low speed controlled access roads within sectors of a city, between collector streets, serving built-up areas, parking and pedestrians unrestricted. Local Preheating Preheating a specific portion of a structure. Local Stress-Relief Heat Treatment Stress-relief heat treatment of a specific portion of a structure. Local Ventilating Pipe A pipe on the fixture side of the trap through which vapor or foul air is removed from a room or fixture. Location A particular place or position. Lock A mechanism for fastening a door with a bolt that requires a key of a particular shape or a combination of movements to work it. Lock Down Seal A reseal to prevent further loss of aggregate if original seal is experiencing aggregate loss. Normally 5mm or 7mm aggregate applied.Also referred to as Pin Down Seal. Lock Plug .Cylinder plug of a lock. Lock Rail The horizontal rail of a door intended to receive the lock case. Lock Stile The door stile to which the lock is applied as distinguished from the hinge stile. Locker Room A room for changing clothes and storing them in lockers, especially for sporting activities. Locker, Clothing See Clothing Locker. Locknut 1. A nut screwed hard up against another to prevent either of them from moving. 2. A nut so constructed that it locks itself when screwed up tight. Locknut, Conduit See Conduit Locknut. Locknut, Grounding See Grounding Locknut. Lockset A device installed in a door that has both a deadbolt and doorknob assembly. Lockwasher A flat, split ring of metal or steel that when tightened with a nut is used to prevent loosening. Locus 1. A position or point. 2. A curve or line formed by all the points satisfying a particular equation. Lodging House Rented living quarters, usually in a private house rather than a hotel. Loft One of the upper floors of an unpartitioned warehouse building. Log A section of tree trunk suitable in length for sawing into commercial lumber. Log Lighter A length of perforated pipe in a fireplace, connected to a valved gas line, used for lighting fires. Loge 1. A small booth or compartment. 2. A box in a theater. 3. A separate forward section of a theater mezzanine or balcony. Loggia An opensided gallery or arcade, especially on upper floors of a building. Logistics The organization and details of carrying out an operation. Long Term Creditors Persons or companies to whom money is owed but not payable for over a year. Long Term Debt Mortgages and loans due in over a year. Long-Oil Varnish Varnish with a large percentage of oil to gum resin, usually more than 25 gallons of oil to 100 pounds of resin; long-oil varnish is more elastic and more durable than short-oil varnish; spar varnish is a typical example of long-oil varnish. Long-Term Burst The internal pressure at which a pipe or fitting will break due to a constant internal pressure held for 100,000 hours. Long-Term Capital Gain The gain upon sale of capital assets that have been held for over 6 months. Longitudinal 1. Running lengthwise. 2. In wood, generally, parallel to the direction of the wood fibers. Longitudinal Bar Any reinforcing bar placed in the long direction of the member. Longshore Parallel to and near the shoreline. Lookout 1. The end of a rafter. 2. The construction which projects beyond the sides of a house to support the eaves. 3. The projecting timbers at the gables which support the rake boards. Lookout A short wood bracket or cantilever that supports an overhang portion of a roof. Lookout A short wood bracket or cantilever to support an overhang portion of a roof or the like, usually concealed from view. Loom Machine on which carpet is woven, as distinguished from other machines on which carpets may be tufted, flocked or punched. Loomed Carpet Carpet made on a modified upholstery loom with characteristic dense low-level loop pile, generally bonded to cellular rubber cushioning; see Woven Carpet. Loop Pile A Wilton or Velvet carpet woven with the yarn uncut; also called Round Wire. Loop Vent This is the same as a circuit vent; the only difference is that the vent loops back and connects with a soil stack or waste stack instead of a vent stack. Loose Fill Insulation Several types of thermal insulation in the form of fibers, granules, or other pieces that can be pumped, poured or placed by hand. Loose Joint Hinge A hinge having but two knuckles, the pin being fastened permanently to one knuckle, the other containing the pinhole, allowing the two parts of the hinge to be disengaged by lifting the door; such hinges are handed. Loose Knot A knot that is not held firmly in place by growth or position and that cannot be relied upon to remain in place. Loose Laid A roofing membrane not attached to the substrate. Loose Steel Lintel Lintel made of structural steel shape (usually angle) that is set loose and built into masonry construction. Loss on Ignition The loss in weight expressed as a percentage, of a sample ignited at a very high temperature (1000 ± degrees C). Lot Line The boundary of a parcel of land. Lots Parcels of land in a recorded subdivision; usually numbered, and shown on a map. Loudness 1. The subjective human definition of the intensity of a sound; human reaction to sound is highly dependent on the sound pressure and frequency. Louver A vented opening into the home that has a series of horizontal slats and arranged to permit ventilation but to exclude rain, snow, light, insects, or other living creatures. Louver An opening with a series of horizontal slats so an ranged as to permit ventilation but to exclude rain, sun. light, or vision. See also Attic ventilators. Louver The part of a shutter which opens and closes. Louver 1 A construction of numerous sloping, closely spaced slats used to prevent the entry of rainwater into a ventilating opening. 2. A kind of window, generally in peaks of gables and the tops of towers, provided with horizontal slats which exclude rain and sno Louver Vent A construction element with equally spaced slots that allow ventilation. Louver, Door See Door Louver. Louver, Metal See Metal Louver. Louver, Penthouse See Penthouse Louver. LouverDrape Blind and shade fabricator known mostly for its vertical blinds. Products include Premierline, Necessities, Fabricel, Carousel, Arielle, and others. A division of Newell. (4110 Premier Drive, Highpoint, NC 27265) Love Wave Transverse vibration of seismic surface wave; see Seismic Wave. Low Boiling Solvent Solvent with a low boiling point such as acetone or methyl alcohol. Low Consistency Plaster A neat (unfibered) gypsum basecoat plaster especially processed so that less mixing water is required than in standard gypsum basecoat plaster to produce workability; this type plaster is particularly adapted to machine application. Low emissivity glass Glass that reduces energy loss by reflecting heat back into a living space. Low Pressure Control Cycling device connected to low-pressure side of refrigeration system. Low Pressure Gauge Instrument for measuring pressures in range of 0 psi to 50 psi (0 kg/cm2to 3.52 kg/cm2). Low Relief Bas relief. Low Rise A building of one or two stories and having no elevator. Low Side That portion of a refrigerating system which is below evaporating pressure. Low-e Glass Low emissivity glass. Low-Energy Power Circuit A circuit which is not a remote-control or signal circuit, but which has the power supply limited in accordance with the requirements of Class 2 remote control circuits. Such circuits include electric door openers and circuits used in the operation of coi Low-Iron Glass Glass formulated with a low iron content so as to have a maximum transparency to solar energy. Low-Lift Grouting A method of constructing a reinforced masonry wall in which the wall is grouted in increments not higher than 4 feet. Low-Pressure Steam Boiler A boiler furnishing hot water at pressures not more than 30 pounds per square inch gauge (2.12 kg/cm2) or steam at pressures not more than 15 pounds per square inch gauge (1.06 kg/cm2). Low-Side Float Valve Refrigerant control valve operated by level of liquid refrigerant in low pressure side of system. Low-Side Pressure Pressure in cooling side of refrigerating cycle. Low-Side Pressure Control Device used to keep low-side evaporating pressure from dropping below certain pressure. Low-Voltage Wiring Wiring used for control, communication, and signal circuits, usually 12 or 24 volts. Lower bank That portion of the streambank below the elevation of the average water level of the stream. Lowest Responsible Bidder The lowest bidder who is considered qualified and responsible. Lozenge A rhombus or diamond figure. LP Fuel Liquefied petroleum used as a fuel gas. LPG Liquefied Propane Gas. LTC Ratio In real estate loans, the Loan to Cost Ratio. Lubrication The use of oil or grease to make parts of machines move easily by reducing friction. Lucite Trademark, used for an acrylic resin or plastic consisting essentially of polymerized methyl methacrylate. Lug Sill A precast window or door sill for a masonry wall which is interlocked with the wall system. Lugs Spacers, or protuberances on the sides of ceramic tiles; these devices automatically space the tile for the grout joints. Lumber Lumber is the product of the sawmill and planing mill not further manufactured other than by sawing, resawing, and passing lengthwise through a standard planing machine, crosscutting to length, and matching. Lumber Sawed parts of a log such as boards, planks, and timber; wood members which are manufactured by sawing, resawing, passing lengthwise through standard planing machine, crosscutting to length, and matching, but without further manufacturing. Lumber Grading See Grade, 1. Lumber, boards Yard lumber less than 2 inches thick and 2 or more inches wide. Lumber, dimension Yard lumber from 2 inches to, but not including, 5 inches thick and 2 or more inches wide. Includes joists, rafters, studs, plank, and small timbers. Lumber, dressed size The dimension of lumber after shrinking from green dimension and after machining to size or pattern. Lumber, matched Lumber that is dressed and shaped on one edge in a grooved pattern and on the other in a tongued pattern. Lumber, shiplap Lumber that is edge-dressed to make a close rabbeted or lapped joint. Lumber, timbers Yard lumber 5 or more inches in least dimension. Includes beams, stringers, posts, caps, sills, girders, and purlins Lumber, yard Lumber of those grades, sizes, and patterns which are generally intended for ordinary construction, such as framework and rough coverage of houses. Lumberjack 1. A logger. 2. A Lumberman. Lumberman 1. One who processes, conveys, or merchandizes lumber. 2. A Lumberjack. Lumen 1. In wood anatomy, the cell cavity. 2. A lighting unit; the amount of light emitted through an opening of 1 square foot, located at a distance of 1 foot from a light source, which emits 1 candlepower in every direction. Lumens Unit of measure for total light output. The amount of light falling on a surface of one square foot. Luminaire A complete lighting unit consisting of a light source, switch, globe, reflector, housing, and wiring. Luminette Vertical blind made of sheer fabric, made by Hunter Douglas. Lump Lime Quicklime as it comes from the kiln. Lump Sum Contract A contract in which the amount to be paid to the contractor is agreed in advance to be a stipulated sum. Lunch Room A room where workers or students eat their lunch. Luncheonette A small restaurant offering light lunches. Lunette An architectural element that has the shape of a crescent or half moon, like an opening in a vault for a window or an alcove for a painting or statue. Luster Fabric Any cut pile fabric woven with surface yarns spun from special types of staple and chemically washed, like hand- woven Oriental fabrics, to give a bright sheen or luster.