Term Definition
Labor and Material Payment Bond 0 likes
Written security document to an owner from a bonding company on behalf of a contractor or subcontractor, guaranteeing payment to the owner if the contractor doesn’t pay for labor, equipment, materials, or services stated in the contract; See Performance Bond and Surety Bond
Labor Union 1 like
A trade union
Laboratory 1 like
A room or building with equipment for examination, experimentation, or analysis
Laboratory Cabinet3 likes
laboratory cabinet
Furniture with drawers or shelves and doors mainly for storage where scientific studies take place, or in commercial and institutional laboratories and testing establishments
Laboratory Counter 3 likes
A level surface in a laboratory where equipment is positioned and where work is done
Laboratory Equipment 0 likes
Implements, devices and tools employed in laboratories
Laboratory Hot Plate 3 likes
A heating appliance used in a laboratory
Laboratory Incinerator 1 like
An apparatus where waste materials are burned in a laboratory
Laboratory Incubator2 likes
laboratory incubator
A device that controls conditions in a laboratory
Laboratory Table2 likes
table, laboratory
A surface on which substances, equipment and tools are stored and used in a laboratory
Lac 2 likes
A natural resin such as seed lac, button lac, and shellac
Laches 3 likes
Unwarranted delay in affirming legal rights, causing loss of the rights
Lacquer 1 like
A liquid composed of shellac in alcohol, or synthetic substances that dries to produce a hard protective coating
Lacunar 1 like
Ceiling consisting of vaults or recessed panels
Lacunaria 3 likes
Recessed panel in a ceiling
Ladder3 likes
A portable piece of equipment with rungs attached to the sides used for climbing up or down
Ladder Bar 1 like
A prefabricated reinforcement used for embedding in the horizontal mortar joints of masonry; parallel crooked side rods joined in a single plane by cross wires producing a ladder-like design
Ladder Cage1 like
ladder cage
A cage-like structure bordering a wall-mounted ladder for safety purposes
Ladder Rung2 likes
ladder rung
A horizontal round component that serves as a step on a ladder
Ladder Step 0 likes
A horizontal flat component of a ladder that serves as a step
Ladder, Pool4 likes
ladder pool
See Pool Ladder
Lag 1 like
Deferred response
Lag Rod 1 like
Large thick rod with a square or hexagonal head
Lag Screw2 likes
lag screw
A large thick wood screw with a square or hexagonal head
Laid Off 5 likes
See Double-Up
Laid-On 3 likes
See Double-Up
Lake Asphalt 2 likes
See Natural Asphalt
Lake Pigment 1 like
Pigment created by placing an organic dye on a base of fine particles of inert or translucent pigment
Lake Sand 3 likes
Sand that has a preponderance of fine, round particles
Lally Column 1 like
Tradename; hollow steel column occasionally filled with concrete
Lamella 2 likes
A structural part of wood, metal, or reinforced concrete crisscrossed to create a vault; curved vaults and domes have been built of wood, steel, and concrete lamellas
Lamina 1 like
The layers of substance in a laminate
Laminar Scale 4 likes
Rust creation in heavy layers
Laminate 3 likes
Produce a product by bonding together two or more layers of substances, such as a plastic laminate
Laminate, Paper-Base 1 like
A multilayer panel produced by compacting resin-impregnated paper sheets into a solid mass
Laminated Glass 3 likes
A glazing substance of exterior layers of glass laminated to and enclosing an inside transparent plastic layer; employed in car windshields and bulletproof glass
Laminated Plastic 1 like
See Plastic Laminate
Laminated Rubber 0 likes
Numerous layers of rubber fused together with adhesive under pressure
Laminated Shingles 0 likes
Shingles that are shake due to additional layers or tabs; also called Architectural Shingles or Three-dimensional Shingles
Laminated Timber 1 like
A construction created by bonding veneer or lumber layers with an adhesive so that the grain is basically parallel
Laminated Wallboard 4 likes
Two or more layers of gypsum board bonded together with an adhesive
Laminated Wood 1 like
A product produced by bonding veneer or lumber layers with an adhesive so that the grain is usually parallel
Laminating 0 likes
Bonding together two or more layers of substances
Laminating Compound 1 like
Regular joint compound or another cementitious material employed to join two or more layers of gypsum board together
Lamination 0 likes
The fusing of layers of material with adhesive
Application of two or more layers of gypsum board
Lamp, Incandescent2 likes
lamp incandescent
See Incandescent Lamp
Lamp, Steri 1 like
See Steri Lamp
Lampback 0 likes
Pigment produced by burning coal tar distillates with insufficient air; not true black
Lampholder1 like
An apparatus that supports an electric lamp and connects it to the circuit conductors
Lanai 0 likes
Porch, veranda, or enclosed patio
Land 3 likes
Earth’s surface containing natural resources
Part of the earth’s solid surface delineated by boundaries or ownership; can be privately or publicly owned
Land Contract 0 likes
A contract for sale of land where title passes to the purchaser when all, or a definite quantity of payments have been made; also called Contract of Sale
Land Plaster 1 like
Roughly ground natural gypsum employed to condition soil
Land Residual 0 likes
A real estate appraisal procedure where a reasonable return on the improvements is first subtracted from the income, the balance is associated with the land
Land Surveyor 0 likes
A person who surveys land
Landing 1 like
A platform between flights of stairs or at the end of a flight of stairs frequently used when stairs change direction; generally no less than 3 feet by 3 feet
Landing Terrazzo 1 like
A staircase landing with terrazzo tile installed on the surface
Landlord 1 like
The owner of property who rents it to a tenant
Landscape 1 like
Natural scenery
Improving a site by changing the terrain, planting trees, shrubs, ground cover, and adding hardscape
Landscape Architect 0 likes
A professional who designs the arrangement of land including vehicle and pedestrian roadways and the planting of ground cover, plants, and trees
Landscape Timber 0 likes
Large, treated lumber lengths for decoration, also performing as soil erosion barriers and retaining wall parts
Lane Joint Cracks 2 likes
Longitudinal separations between two paving lanes caused by a weak seam between adjoining applications in the pavement paths
Langly 1 like
Solar radiation measurement that equals 1 calorie per square centimeter
Lantern1 like
An elevated structure glazed to let in light on a roof
Lap 0 likes
Cover the surface of a shingle or roll with another
Lap Joint 3 likes
A joint made by placing one structure partially over another and bonding the overlapped parts.
Lap Siding 2 likes
See Bevel Siding
Lapping 0 likes
Smoothing a metal surface to high level of accuracy with a fine abrasive
Laser2 likes
A machine that produces an intense beam of monochromatic infrared, visible or ultraviolet radiation employed in industry and medicine; used in construction to create accurate sightings, and plumb and level vertical and horizontal alignments
Acronym for Light Amplification by Stimulated Emission of Radiation
Latch3 likes
A beveled metal tongue controlled by a spring-loaded knob or lever that enables door closure by engaging the locking mechanism without a key. Contrasts with dead bolt
Latent Ambiguity 1 like
A term of a contract that appears clear but becomes ambiguous due to external circumstances
Latent Defect 2 likes
Construction defect that is not distinguishable with normal observation
Latent Heat 2 likes
Heat that changes the state of a substance from a solid to a liquid, or a liquid to a gas
Latent Heat Gain 3 likes
Adding heat to an enclosure by increasing the moisture content
Latent Heat of Condensation 1 like
Quantity of heat lost by a pound of a material when it changes from a gas to a liquid
Latent Heat of Vaporization 0 likes
Quantity of heat needed per pound of a substance to change its state from a liquid to a gas
Lateral (Electric, Gas, Sewer, Telephone, and Water) 2 likes
Underground trench and related services (electric, gas, telephone, sewer and water lines) that will be submerged within the trench
Lateral Brace 3 likes
A structural brace that resists lateral motion of a truss or beam
Lateral Branch 0 likes
See Horizontal Branch
Lateral Force 2 likes
A force usually horizontal, such as wind, earthquake, or soil pressure against a foundation wall
Lateral Force Coefficients 2 likes
Factors applied to a structure’s weight to define lateral force for seismic design
Lateral Load 1 like
The horizontal part of the load created by an arch, vault, dome, or frame
A horizontal load placed on a structure such as wind or earthquake
Lateral Pressure 1 like
Horizontal pressure against the side of a high foundation wall such as the force of soil or wind
Lateral Slip Fault 2 likes
A fault whose relative displacement is only horizontal
Lath 0 likes
Slender wood, gypsum, metal, or insulating board that is secured to a building frame performing as a base for plaster, tiles, or shingles
Lattice4 likes
Open crisscrossed wood framework or metal strips that have regular, patterned spaces
Leasehold Improvements 1 like
A term used to describe tenant improvements for construction in retail stores and office buildings
Ledger for a Structural Floor 1 like
Wood frame lumber perimeter part; ledger for a structural floor is the part that bolts onto the face of a foundation wall and supports the wood structural floor
Ledger Strip 4 likes
Lumber strip nailed along the bottom of a girder side on which supporting beams or joists rest
Leech Field 0 likes
Process of treating and disposing of sewage in rural areas that do not have access to a municipal sewer system; sewage is filtered and ultimately dispersed into an area of the lot known as a leech field
Let-in Brace 1 like
One inch thick boards inserted diagonally into notched studs; additionally an L-shaped, 10 foot metal strap installed early by the framer to support an exterior wall or wall corner
Level3 likes
Horizontal; also a device that ascertains level
Level Payment Mortgage 1 like
Mortgage with the same monthly payments over the lifespan of the loan
Lien 2 likes
An impediment that usually uses real or personal property as the security for payment of a debt
Lien Release 2 likes
Document from a contractor to the owner that discharges a mechanic’s or material lien after the issues have been resolved
Lien Waiver 1 like
Document from a contractor, subcontractor, material supplier or construction professional who has lien rights against an owner’s property, discharging all or part of those rights
Lien waivers are usually employed to process progress payments to prime contractors or subcontractors as a Conditional Lien Waiver, Unconditional Lien Waiver, and Final Lien Waiver
Lien, Mechanic’s or Material 2 likes
The right to take, hold or sell an owner’s property to satisfy outstanding debts to an authorized contractor for labor, materials, equipment or services; See Preliminary Lien Notice
Light 2 likes
Space in a window sash for a pane of glass; also a pane of glass
Limit Switch1 like
limit switch
Safety control that automatically turns off a furnace when it gets too hot; also control blower cycles
Lineal Foot 0 likes
A unit to measure lumber that equals 1 inch thick by 12 inches wide by 12 inches long Examples: 1 inch x 12 inches x 16 feet = 16 board feet, 3 inches x 12 inches 16 inches = 48 board feet
Lintel 1 like
Horizontal structural component that supports the load over an opening such as a door or window
Load Bearing Wall 2 likes
Includes all external walls and any internal wall aligned above a support beam or girder; usually, a wall that has a double horizontal top plate
Loan 1 like
Amount borrowed
Loan to Value Ratio 4 likes
The ratio of the loan amount to the property valuation expressed as a percentage; if a borrower wants a loan of $300,000 on a property valued at $600,000 it has a 50 percent loan to value rate; if the loan were $450,000, the LTV would be 75 percent; the higher the loan to value, the greater the lender’s perceived risk
Lookout 1 like
Short wood bracket or cantilever supporting the overhang part of a roof
Louver4 likes
A vented opening into a home with a series of horizontal slats that allow ventilation but exclude rain, snow, light, and insects
Lumens 0 likes
Unit to measure total light output; amount of light on a surface of one square foot
Lump Sum Bid 0 likes
Single sum of money to complete a construction without a cost breakdown
Lump Sum Contract 2 likes
Contract between an owner and contractor where the owner agrees to pay the contractor a specific amount of money for completing a scope of work made up of various unspecified items
Product of the day


A structural, mathematical solid shaped like a circle with a hole in it



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