L - Technical Dictionary


Labelled Door (or Frame)                         
A door or frame that conforms to all the applicable requirements, in respect to fire resistance, of nationally recognised testing authority, and bears a label designating that fire rating. Also known as Fire-Rated Doors.

Ladder-Back Chair                                    
A chair made with a back of horizontal rails between the uprights.

Lagging                                                      
Insulation used to prevent heat diffusion and reduce noise made by building services such as air conditioning and plumbing. Generally it comes in the form of plaster lining that fits over the service ducts or piping. also also the name for when a computer takes a 10-15 min coffee break.

Laminated Glass                                       
Two or more layers of glass separated by a thin layer of flexible clear plastic which holds the glass in place when it breaks, reducing the risk of injury from flying glass. Laminated annealed glass does not have the impact resistance of tempered glass, so will crack under impact. However it is possible to laminate tempered glass offering the benefits of both types of glass. Glass which has been subjected to a special process of bonding two or more sheets together with one or more sheets of a special plastics interlayer.

Laminated Safety Glass                            
Two or more layers of tempered glass separated by a thin layer of flexible clear plastic which holds the glass in place when it breaks, reducing the risk of injury from flying glass.

Laminated Timber                                     
Layers of timber glued together to increase rigidity or create a multi-coloured effect.

Landing                                                      
A platform between flights of stairs or at the termination of a flight of stairs. Often used when stairs change direction.

Landscape Architect                                 
A person who designs the location of buildings, roads, and walkways, and the arrangement of flowers, shrubs, and trees. Landscape architecture was pioneered by practitioners such as Frederick Law Olmsted, who designed New York’s Central Park, to integrate open space with the built environment of a major city.

Landscape Drawing                                  
Drawing which shows the composition and processing of the ground for roads, planted areas, external installations, etc.

Lantern                                                      
A small circular or polygonal structure erected on a dome or roof to let in light.

Lap Joint                                                    
A joint in which the structural units being joined override each other.

Latch                                                         
A movable bar sliding or falling into a catch, the movable part being operated by a handle or lever and not by a removable key.

Latchbolt                                                    
A lock component having a bevelled end that projects from the lock front, but may be forced back into the lock case by end pressure or drawn back by action of the lock mechanism. When the door is closed, the latchbolt projects into a hole provided in the strike, holding the door in a closed position.

Lath and Plaster                                       
Thin strips of wood nailed to interior surfaces such as studs and ceiling joists and covered with plaster.

Lattice                                                        
An open framework of criss-crossed wood or metal strips that form regular, patterned spaces.

Layer                                                         
A Logical grouping of data within a CAD drawing file which can be turned on and off as required.An organisational attribute of entities in a CAD data file used to separate data in order to manage and communicate that data and to control visibility on the computer screen and on plotted drawings.

Layering System                                       
The method established to retrieve specific data from a CAD drawing file. Examples: The AIA CAD Layer Format Numbered CAD Layering System

Layout Drawing                                         
Drawing showing the location of sites, structure, buildings, spaces, elements, assemblies or components (synonym = location drawing).

Layout Plan                                               
Plan that shows the use of a site plan or area.

Lazy Susan                                               
A revolving tray or stand of wood or metal.

Leadlight                                                    
Decorative glazing using small rectangular, diamond or other shaped pieces of glass, often coloured, and set in lead strips.

Leaf (of a Pair of Doors)                           
One of the two doors forming a pair or a double door.

Leech Field                                                
A method used to treat/dispose of sewage in areas not accessible to a municipal sewer system.

Left Hand                                                  
To describe a component or design of a window. Always taken viewing the product from the outside.

Lego                                                          
A toy consisting of small interlocking plastic pieces, principally bricks for constructing model buildings, etc.

Level                                                          
A horizontal position or a region (Eg Level 1). A height in relation to a datum:
  • Above Finished Level (AFL)
  • Above Structural Level (ASL)
  • Existing Level (XL)
  • Finished Level (FL)
  • Structural Level (SL)
  • Finished Floor Level (FFL)
  • Natural Ground Level (NGL)
  • Finished Ground Level (FGL)
Life Cycle Cost                                          
Include all costs incident to the planning, design, construction, operation, maintenance and demolition of a facility, all in terms of present value.

Light                                                           
A compartment of a window, usually separated by mullions.

Lighting Drawing                                       
Drawing which specifies the type and location of lighting, lighting equipment and lighting system circuitry.

Linkway                                                     
An enclosed connection between buildings.

Lintel                                                          
A horizontal structural member that supports the load over a door, window, or other opening.

Lion's-Paw Foot                                        
A leg terminal or foot carved in the shape of a lion's paw. It was a popular Regency and Empire motif.

List of Defects                                           
A listing of those portions of the work that were not constructed correctly or are defective.

List of Deficiencies                                    
A listing of those portions of the work that were contracted for, but are missing.

Load                                                          
An external force. The term load is sometimes used to describe more general actions such as temperature differentials or movements such as foundation settlements.

Load-Bearing                                             
Intended to resist vertical forces additional to its own weight.

Load-Bearing Wall                                    
A wall that supports weight from a floor or ceiling above it.

Loading/Delivery Bay                                
An area in a building such as a factory, warehouse, supermarket, hotel or theatre, where goods are unloaded from delivery vehicles. Please refer to "Loading dock" for more information.

Loading/Delivery Dock
A recessed bay in a building or facility where trucks are loaded and unloaded, commonly found on commercial and industrial buildings, and warehouses in particular. Loading docks may be exterior, flush with the building envelope, or fully enclosed. They are part of a facility's service or utility infrastructure, typically providing direct access to staging areas, storage rooms, and freight elevators. In order to facilitate material handling, loading docks may be equipped with the following:
  • Bumpers - protect the dock from truck damage, may also be used as a guide by the truck driver when backing up.
  • Dock leveler - a height-adjustable platform used as a bridge between dock and truck, can be operated via mechanical (spring), hydraulic, or air powered systems.
  • Dock lift - serves same function as a leveler but operates similar to a scissor lift to allow for greater height adjustments.
  • Dock seals - compressible foam blocks against which the truck presses when parked; seals are used at exterior truck bays in colder climates where this will provide protection from the weather.
  • Truck or vehicle restraint system - a strong metal hook mounted to the base of the dock which will hook to the frame or bumper of a trailer and prevents it from rolling away during loading operations, can be operated via manual, hydraulic, or electrical systems; this system can replace or work in conjunction with wheel chocks.
  • Dock light - a movable articulating light mounted inside the dock used to provide lighting inside the truck during loading operations.

Lobby                                                       
An entry foyer, small hall or waiting-room serving as a common entrance.

Lock Stile (of a Door)                               
The vertical member of a door to which the lock mechanism is applied, as distinguished from the hinge stile.

Loggia                                                       
A architectural feature, often a gallery or corridor, where the facade is open to the air on one side. Supported by columns or pierced openings in the wall. Originally of Italian design A gallery open on one or more sides, sometimes pillared. It may also be a separate structure, usually in a garden. An open arched porch attached to a larger structure.

Longitudinal Section                                
Section in which the cutting plane is situated in the longitudinal direction of the object.

Louis XIV Style                                        
The rich formal style of decoration in vogue under the Sun King, Louis XIV of France (1643- 1715). It combines elements of Italian baroque with devices taken from the standard classical repertoire of ornament as well as innovations such as Boulle marquetry.

Louis XV Style                                         
The French version of Rococo, popular between 1720 and 1750. Its principle feature is its extensive use of asymmetry and of ormolu.

Louis XVI Style                                        
Early neo-classical style of decoration already popular when Louis XVI came to the throne in 1774. Furniture became more rectilinear and geometric, e.g. cabriole legs gave way to cylindrical or square ones. Also in reaction to rococo styles decoration became more restrained, e.g. floral themes were replaced by architectural motifs.

Lounge                                                     
A resort of loungers; a kind of sofa, especially with a back and one raised end. A sitting-room in a private house; a room in a public building for sitting or waiting, often providing refreshment facilities

Louvre                                                      
A horizontal arrangement of overlapping and downward slanting timber or glass slats to admit air but exclude rain (often floor to ceiling in tropical climates).

Louvre Window                                        
Fixed or adjustable slats (glass, timber or aluminium) which allows ventilation. Can be either horizontal or vertical.

Louvres                                                    
Fixed or adjustable slats (glass, timber or aluminium) which allows ventilation. Can be either horizontal or vertical.

Low-Emissivity Glass                     
Specially coated glass that prevents the transfer of heat.

Lowlight                                                    
The portion of the window that is below the transom.

Lug                                                           
Bracket used to fasten window frame into building.

Luminance Level                                      
The amount of light in an area.

Lump Sum Contract                                 
A contract where the contractor has undertaken to be responsible for executing the whole of the contract work for a stated total sum which may be fixed or subject to rise and fall.








Need drafting work?
We are having great success with Freelancer.com. With this website we can win all types of drafting work. People from all over the world are looking for freelancers skilled in AutoCAD, Revit, Civil 3D and Microstation, are you one of those people? If so you can live the freelancer lifestyle! and work from any location you want too. Freelancer.com, it works really well - we like it - and we believe you will too.

Looking for CAD drafters?
With modern construction, software and increased legal requirements, we often require specialized assistance with our projects. Putting skilled staff on full time is not always economically feasible for small businesses. Freelancer.com solves this problem. On this website you can engage skilled drafters. Either on fixed prices for specific tasks, or reasonably priced hourly rates for longer term contracts.

E-book: AutoCAD Block Best Practices
We draw repetitively when using AutoCAD. If we manage the drawing elements as reusable contents, it will increase our productivity significantly. Not only can we draw faster, we can add information to our blocks. Which allows us to generate useful reports. This is what Edwins e-book entitled AutoCAD Block Best Practices is all about. Yes, increase your productivity with the block!