labeled: Devices, equipment and materials to which have been affixed a label, seal, symbol or other identifying mark of product evaluation.
labor hour: A standard in which one person's labor is performed in one hour.
ladder: A portable or fixed (permanently attached) structure consisting of two long sides crossed by parallel rungs and used to climb up and down.
laminate: A laminated product, such as plywood.
laminated glass: Two or more lites of glass permanently bonded together with one or more inter-layers.
laminated shingles: Shingles that have added dimensionality because of extra layers or tabs, giving them a shake-like appearance. Also called architectural shingles and three-dimensional shingles.
laminating: Bonding together two or more layers of materials.
landing: A platform between flights of stairs or at the termination of a flight of stairs.
lap: To extend one material partially over another; also, the distance so extended.
lap cement: An asphalt-based cement used to adhere overlapping plies of roll roofing.
lateral: The underground trench and related services or utilities (electric, gas, telephone, sewer and water lines) that are buried within the trench.
lath: A building material of wood, metal, gypsum or insulating board that is fastened to the frame of a building that acts as a plaster base.
lath and plaster: The most common wall finish prior to the introduction of drywall. Thin wood strips (lath) were nailed onto the framing as a base for the sand/lime plaster.
lattice: A framework of crossed wooden or metal strips.
lavatory: Bathroom or washroom sink.
leach field: A septic drainfield; a method by which sewage is permitted to be filtered and discharged into the ground near a home, typical in rural areas not accessible to a municipal sewer system.
lead: A malleable metal once extensively used for flashings.
lead-based paint: Lead is a highly toxic heavy metal that was used in exterior and interior household paint before it was outlawed in the U.S. in 1978. Exposure or ingestion to disturbed lead-based paint can cause a range of short- and long-term health problems, from behavioral issues and learning disabilities, to seizures and death. Children under 7 are at greatest risk.
lean-to roof: The sloping roof of a building addition having its rafters or supports pitched against and supported by the adjoining wall of a building.
ledger: Dimensional lumber attached to a building framing and used for supporting the section of a deck adjacent to the building.
ledger strip: A strip of lumber nailed along the bottom of the side of a girder on which joists rest.
let-in brace: Nominal 1 inch-thick boards applied diagonally into notched studs.
level: (1) Term used to describe any horizontal surface whereby all sides are at the same elevation. (2) A carpenter's level is a tool used to check for level.
level-payment mortgage: A mortgage with identical monthly payments over the life of the loan.
leveling rod: A rod with graduated marks for measuring heights or vertical distances between given points and the line of sight of a leveling instrument. It is longer than a yardstick and held by a surveyor in a vertical position to mark elevations.
lien: An encumbrance secured by real or personal property for repayment of a debt or discharge of an obligation.
life expectancy: Average service life or functional period in years, assuming regular maintenance.
light: (1) A source of light, especially a lamp, lantern, or an electric lighting fixture, either permanently installed or portable; the illumination emitted by a source of light. (2) The space in a window sash for a single pane of glass; a pane of window glass (variation of lite).
limit switch: A safety control that automatically shuts off a furnace if it gets too hot; must also control blower cycles.
linear foot: A unit of measure for lumber equal to 1 inch thick by 12 inches wide by 12 inches long. Examples: 1 inch x 12 inches x 16 feet = 16 board feet; 2 inches x 12 inches x 16 feet = 32 board feet.
lintel: A horizontal structural member that supports the load over an opening, such as a door or window.
liquid-applied membrane: Generally applied to cast-in-place concrete surfaces in one or more coats to provide fully-adhered, waterproof membranes that conform to all contours.
liquidated damages: A monetary amount agreed upon by two parties to a contract prior to performance under the contract that specifies the amount either party owes the other if that party defaults.
listed: Equipment, materials or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with the evaluation of products or services that maintains periodic inspection of the production of listed equipment or materials, or periodic evaluation of services, and whose listing states that the equipment, material or service meets appropriate designated standards, or has been tested and found suitable for a specified purpose.
lite: A pane of window glass (variation of light).
live load: Loads produced by use and occupancy of a building or other structure, not including construction or environmental loads, such as wind load, snow load, ice load, rain load, seismic load, or dead load.
load-bearing wall: A wall that supports its own weight and some other structural elements of a house or building, such as the roof and ceiling structures.
loan: A sum of money lent at interest.
loan-to-value ratio: The ratio of a loan amount to the property valuation expressed as a percentage. For example, 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 higher the loan to value, the greater the lender's perceived risk. Loans above normal lending LTV ratios may require additional security.
lookout: A short wooden bracket or cantilever, usually concealed from view, that supports an overhanging portion of a roof or similar structure.
loose-laid: In roofing, a membrane laid loosely and not adhered over a roof deck or berm.
lot: A parcel of ground with boundaries determined by the county.
louver: A horizontal slat. A louvered window is constructed of a series of horizontal slats in a window space arranged so as to permit ventilation but prevent the entry rain or sunlight. Louvers are also used in attic ventilators, which are mechanical fans that move large amounts of air at a low velocity.
low-slope application: A method of installing asphalt shingles on roof slopes between 2 and 4 inches per foot.
lumber: The product of a sawmill and planing mill not further manufactured other than by sawing, re-sawing, and passing lengthwise through a standard planing machine, cross-cutting to length, and matching.
lumens: Unit of measure for total light output; the amount of light falling on a surface of 1 square foot.