Modular Industry Glossary


A passageway or means of approach to a room or building; a corridor between rooms; also a term used in building construction referring to points at which concealed equipment may be reached for inspection and repair.


The condition resulting from the inclusion of appropriate architectural elements to permit unrestricted entrance to, exit from, and use of buildings and facilities.

Accordion Door

Folding doors supported by carriers with rollers, which run on a track; the doors fold up in a manner similar to the bellows of an accordion, hence the name.

Acoustical Board

Any type of special material, such as insulating boarding, used in the control of sound or to prevent the passage of sound from one room to another.


Material added to cement or the concrete mix to increase workability, strength, or imperviousness to lower freezing point (e.g. anti-freeze). Accelerators, plasticizers and air-entraining agents are admixtures.


Architect/Engineer; normally engaged by an Owner.

Air Changes per Hour (ACH)

The number of times per hour a volume of air, equivalent to the volume of space, enters that space.

Air Conditioner

One or more factory made assemblies that include an evaporator or cooling coil and an electrically driven compressor and condenser combination, and may include a heating function.

Air Conditioner – Window

Self-contained room conditioner arranged to be supported in, or connected with a window opening, circulating outside air over the high side and room air over the low side.

Air Conditioning

The process of treating air to meet the requirements of a conditioned space by controlling its temperature, humidity, cleanliness and distribution.

Aluminum Window

A glazed window with aluminum sash and muntins.


1. In prestressed concrete, to lock the stressed tendon in position so that it will retain its stressed condition; in precast concrete construction, to attach the precast units to the building frame; in slabs on grade or walls, to fasten to rock or adjacent structures to prevent movement of the slab or wall with respect to the foundation, adjacent structure or rock.

2. That bolt or fastening device which attaches to the anchorage.

3. An egg-shaped ornament alternating with dart-like tongue used to enrich a molding.


In post-tensioning, a device used to anchor the tendon to the concrete member; in pre-tensioning, a device used to anchor the tendon during hardening of the concrete; in pre-cast concrete construction, the devices for attaching pre-cast units to the building frame; in slab or wall construction, the device used to anchor the slab or wall to the foundation, rock, or adjacent structure. Sometimes called a deadman.

Anchorage bolt

A bolt with the threaded portion projecting from a structure generally used to hold the frame of a building secure against wind load.

Angle of Maximum Candela

The direction in which the luminaire emits the greatest luminous intensity.


American National Standards Institute

Anti-corrosive Paints

Coatings formulated and recommended for use in preventing the corrosion of ferrous metal substrates.

Architectural Barrier

Any physical conditioning of a building or facility that creates unsafe or confusing conditions or prevents accessibility and free mobility.

Asbestos Shingles

A type of shingle made for fireproof purposes. The principal composition of these shingles is asbestos, which is non-combustible, non-conducting and chemically resistant to fire.

Asphalt Shingles

Composition roof shingles made from asphalt impregnated felt covered with mineral granules.


Also called “Earth Drill”; a horizontal rotating drill having a screw thread-type bit that carries cuttings up and away from the face.

Automatic Fixture Sensors

Motion sensors that automatically turn on/off lavatories, sinks, water closets and urinals.  Sensors may be hard-wired or battery operated.


A roof-like shelter extending over a doorway, window, porch, etc. that provides protection from the sun or rain.


Earth or other material used to replace material removed during construction.


A horizontal decorative element used to cover the joint between a wall and floor.

Baseline Building Performance

The annual energy cost for a building design intended for use as a baseline for rating above standard design.

Basis of Design (BOD)

Includes design information necessary to accomplish the owner’s project requirements including system descriptions, indoor environmental quality criteria, other pertinent design assumptions (such as weather data), and references to applicable codes, standards, regulations, and guidelines.


Quantity of concrete or mortar mixed at one time.


A narrow strip of wood or metal used to cover vertical joints between boards or panels.

Batten Boards

Pairs of horizontal boards nailed to wood slates; used as a guide to elevations and to outline the building.

Bearing Wall

A wall that supports any vertical load in a building as well as its own weight.


A point of known or assumed elevation used as a reference to determine other vertical elevations.


Plant material such as trees, grasses, and crops that can be converted to heat energy to produce electricity.


Does not have a single definition that is accepted nationwide. Wastewater from toilets and urinals is, however, always considered blackwater.

Wastewater from kitchen sinks (perhaps differentiated by the use of a garbage disposal), showers, or bathtubs may be considered blackwater by state or local codes.  Project teams should comply with a blackwater definition as established by the authority having jurisdiction in their areas.

Blinds (Shutters)

Light wood sections in the form of doors to close over windows to shut out light, give protection, or add temporary insulation. Commonly used now for ornamental purposes, in which case they are fastened rigidly to the building.


Building Officials’ Conference of America

Bond Breaker

A material used to prevent adhesion of newly-placed concrete to the substrate or additional concrete.

Bow Roof

A roof supported by bowstring trusses.

Bow String Truss

A roof structural member having a bow-shaped element at the top and a straight or combined element connecting the two ends. A pre-assembled unit consisting of a horizontal bottom chord and a curved top chord. The top and bottom members are secured by either metal web members or lumber. The width of the bow truss is equal to the unit width and is normally 16” on-center.


A covered passage, open at each end, passes through a house or between two structures increasing ventilation and adding an outdoor living effect.

Brick Veneer

The outside facing of brickwork used to cover a wall built of other material; an outer covering of a four-inch brick wall tied to a wood-frame wall.

Building Codes

Laws designed to provide minimum standards to safeguard life, property, and public welfare.

Building Official

An officer or other designated authority charged with the administration and enforcement of the code, who has the power of a law enforcement officer. The official has the power to render interpretations in conformance with the code intent and purpose.

Building Envelope

The exterior surface of a building’s construction – the walls, windows, roof, and floor.


A rigid assembly of reinforcement steel ready for placing in position within a concrete form.


A housing for a recessed fixture.


An ornamental roof-like covering supported by posts or suspended from a wall; a sheltering member, as over a niche, a doorway, or a seat of honor.

Carpet Density

The number of pile tuft rows, per inch, for the length of the carpet.

Carpet Pitch

The number of yarns across the width of the carpet expressed in yards ends per 27 inches of width.


A type of window having a sash with hinges on the side, allowing the window to open horizontally.

Casement Door (French Door)

A hinged door or pair of doors almost completely glass.


The framework around a window or door.


Mortar or concrete is deposited in the place where it is required to harden, as opposed to “pre-cast”.


The process of filling seams with mastic material to prevent leaking.


Interior finish of an overhead surface.

Central Air Conditioner

An air conditioner that provides service to an entire structure from a single, central source.

Central Heating

A system of heating in a building that depends upon one source with distribution ducts.

Ceramic Tile

A thin, flat piece of fired clay, usually square and attached to walls, floors, or countertops with cement or other adhesives creating durable, decorative, and dirt-resistant surfaces.

Certificate of Occupancy

The permission that allows a building to be occupied and used for its intended purpose.  Obtained after all construction is complete and all inspections have been successfully done.


A document that tracks the movement of a wood product from the forest to a vendor and is used to verify compliance with FSC guidelines.  A “vendor” is defined as the company that supplies wood products to project contractors or subcontractors for on-site installation.

Chair Rail

A plain or molded strip on a wood or plaster wall as protection against chair backs.

Chlorofluorocarbons (CFC’s)

Hydrocarbons that deplete the stratospheric ozone layer.

Cinder Block

a.k.a. CMU or Concrete Masonry Unit.

Clear Span

The distance, or clear and unobstructed opening, between two supports of a beam; always less than the effective span.


Concrete Masonry Unit: Type of building construction utilizing cinder block or concrete block.


Carbon dioxide

Cohesion of Soil

The quality of some soil particles to be attracted to similar particles. It is manifested in a tendency to stick together, as in clay.


A compression member, vertical or nearly vertical, the width of which does not exceed four times its thickness and the height of which exceeds four times its least lateral dimension.

Column Footings

Concrete footings reinforced with steel pads or unreinforced; used as supports for columns which in turn carry the load of beams which serve as supports for the superstructure of a building.

Comfort Criteria

Specific original design conditions that shall at a minimum include temperature (air, radiant, and surface), humidity and airspeed as well as outdoor temperature design conditions, outdoor humidity design conditions, clothing (seasonal), and activity expected.

Commissioning (Cx)

The process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained to perform in conformity with the owner’s project requirements.

Commissioning Plan

A document defining the commissioning process, which is developed in increasing detail as the project progresses through its various phases.

Commissioning Specification

The contract document that details the objective, scope, and implementation of the construction and acceptance phases of the commissioning process as developed in the design-phase commissioning plan.

Commissioning Team

Includes those people responsible for working together to carry out the commissioning process.


An interacting population of individuals living in a specific area.

Composite Wood

A product consisting of wood or plant particles or fibers bonded together by a synthetic resin or binder (i.e., plywood, particle-board, SOB, MDF, Composite door cores.)  For the purposes of LEED requirements, products must comply with the following conditions:

1. The product is inside the building’s waterproofing system.

2. Composite wood components used in assemblies are included (e.g., door cores, panel substrates, plywood sections of I-beams).


A composite material that consists essentially of a binding medium within which are embedded particles or fragments of aggregate, Portland cement, and water. When set it attains hardness and strength similar to stone.

Conditioned Space

The part of a building that is heated or cooled, or both, for the comfort of occupants.

Construction and Demolition (C&D) Debris

Includes waste and recyclables generated from the construction, renovation, and demolition or deconstruction of pre-existing structures.  Land clearing debris including soil, vegetation, rocks, etc. is not to be included.

Construction IAQ Management Plan

A document specific to a building project that outlines measures to minimize contamination in the building during construction, and to flush the building of contaminants prior to occupancy.


An unwanted airborne constituent that may reduce the acceptability of the air.

Contour Lines

Lines that are drawn to show topography.  Contour lines show specific elevations above sea level.

Conventional Irrigation

Refers to the most common irrigation system used in the region where the building is located.  A common conventional irrigation system uses pressure to deliver water and distributes it through sprinkler heads above the ground.


Projection at the top of a wall; a term applied to construction under the eaves or where the roof and side walls meet; the top course, or courses, of a wall when treated as a crowning member.


A long passage wall or hall connecting parts of a building.


A concave molding, the curved junction between a ceiling and a sidewall.

Cove Base

Made of vinyl, rubber, tiles, and/or metal in a variety of heights and shapes for a wide range of sheet goods and tile installations.

Crawl Space

In cases where buildings have no basements, the space between the first floor and the surface of the ground; large enough for someone to crawl through for repairs and installation of utilities. Also called a crawlway.

Crown Molding

A molding used above eye level; usually the corner molding under the roof overhang or at the wall/ceiling connection on the interior.


The controlled admission of natural light into a space through glazing with the intent of reducing or eliminating electric lighting.  By utilizing solar light, daylighting creates a stimulating and productive environment for building occupants.

Dead Bolt Lock

A lock worked only by key from both sides or combination key and lever and having no doorknobs.


An exterior floor system generally above grade.

Deed Restrictions

Development requirements that travel with the property title from owner to owner.

Development Footprint

The area on the project site that has been impacted by any development activity.  Hardscape, access roads, parking lots, non-building facilities, and building structure are all included in the development footprint.

Diffuse Reflection

Light reflection off a surface to produce a uniform light in all directions. Light reflection from a surface rather than radiating directly from a light source.

D.I.G. Window

The use of two sheets of glass with an inert gas sealed into the space between them to provide insulation against the passage of heat.

Distribution Box/Panel

In electricity, an insulated board from which connections are made between the main feed lines and branch lines.

Direct Line of Sight to Perimeter Vision Glazing

The approach used to determine the calculated area of regularly occupied areas with direct line of sight to perimeter vision glazing.  The area determination includes full-height partitions and other fixed construction prior to installation of furniture.

Double Hung Window

A type of window containing two movable sash sections that open vertically.

Down Spout

A vertical pipe used to drain rainwater from a roof.

Drainage Easement

An area set aside where no construction can be built, to allow for permanent site drainage.

Drip Cap

A molding placed on the exterior top part of a door or window to cause water to drip beyond the outside of the frame.

Drip Irrigation

A high-efficiency irrigation method in which water is delivered at low pressure through buried mains and sub-mains.  From the sub-mains, water is distributed to the soil from a network of perforated tubes or emitters.  Drip irrigation is a type of micro-irrigation.

Drop Ceiling

A false or lowered ceiling, typically a T-Bar system.


A wall constructed of material that is put in place without the use of plaster. Preformed sheets such as gypsum wallboard.

Dual-Duct System

An HVAC system using two ducts, one for supply and one for return air. The air from these ducts is blended in mixing boxes before distribution to each location.


1. In post-tensioning, a hole made in a post-tensioned member to accommodate a tendon.

2. In a building, usually round or rectangular metal or insulated pipe for distributing the conditioned air to rooms from a conditioning device.

Earth Drill

a.k.a. “auger”; a horizontal rotating drill having a screw thread-type bit that carries cuttings up and away from the face.


A basic unit of nature that includes a community of organisms and their non-living environment linked by biological, chemical, and physical processes.


That part of a roof that projects over the sidewall.

Elephant Trunk

An articulated tube or chute used in concrete placement. Also called a “drop chute”.

Embodied energy

The energy that is used during the entire life cycle of the commodity for manufacturing, transporting, and disposing of the commodity as well as the inherent energy captured within the product itself.

Energy Conservation Measures (ECMs)

Installations of equipment or systems, or modification of equipment or systems, for the purpose of reducing energy use and/or costs.


The rating of a building earns using the ENERGY STAR Portfolio Manager to compare building energy performance to similar buildings in similar climates.  A score of 50 represents average building performance.

Environmental Attributes of Green Power

Include emission reduction benefits that result from green power being used instead of conventional power sources.

Environmentally Preferable Products

Products identified as having a lesser or reduced effect on health and the environment when compared with competing products that serve the same purpose.

Erosion Controls

Temporary measures taken to prevent environmental damage from the construction site “run-off”.


Any man-made cavity or depression on the earth’s surface; formed by earth removal.

Extra Light

An illuminating sign above an exit identifying it as an exit.

Exterior Wall

Any outside wall or vertical enclosure of a building other than a party wall.


Soil or other materials used to raise grade.

Fire Door

A metal-sheathed door that will resist fire often held from sliding shut by a fusible link. Doors designed to resist standard fire tests and labeled for identification.


Any material or combination of materials built to protect structural members so as to increase their fire resistance.

Fire Wall

Any wall which subdivides a building to resist the spread of fire and which extends continuously from the foundation through the roof.

Flame Spread Classification

A standard test rating of fire-resistive and protective characteristics of building material.

Flanking Window

A window set beside an outside door that is often used to light a hallway.

Flat Roof

A roof having only minimal slope for drainage.

Flexible Metal Roofing

Roof covering of flat metal sheet.

Flood Plain

The name for an area outlined by an established elevation that water typically covers during uncommonly heavy or consistent rains.

Flooring Tiles

Concrete or clay tiles set in cement mortar, bituminous, or other adhesive. For a more sound absorbent, heat-insulating, decorative, or comfortable walking surface, linoleum, glass, cork, rubber, asphalt, or plastic tiles are used.

Fluorescent Lighting

A light source in which light is produced by a fluorescent power, phosphor coated on the inner surface of a glass tube. A mercury vapor arc between electrodes sealed into each end of the tube generates ultra-violet radiation that is changed by the phosphor into visible light.


A door, any size not paneled, having two flat surfaces; flush doors are frequently of various types of hollow core construction.

Flush Tank

A tank that holds water for flushing one or more plumbing fixtures.

Fly Ash

The solid residue derived from incineration processes.  Fly ash can be used as a substitute for Portland cement in concrete.

Folding Doors

The assembly of two or more hinged leaves which, when straightened in a line, can close the opening.

Foot Candle (Ft-C)

A quantitative unit for measuring illumination. It is approximately the illumination produced by a plumber’s candle at a distance of one foot.


A naturally occurring VOC found in small amounts in animals and plants, but is carcinogenic and an irritant to most people when present in high concentrations – causing headaches, dizziness, mental impairment, and other symptoms.  When present in the air at levels above 0.1 ppm (parts per million), it can cause watery eyes, burning sensations in the eyes, nose, and throat; nausea; coughing; chest tightness; wheezing; skin rashes; and asthmatic and allergic reactions.


The trade name for a hard durable plastic laminated sheeting used for table, sink, and countertops or for wall covering; resistant to heat and chemicals.

Foundation Wall

A wall below the floor nearest grade as a support for a wall, pier, column, or another structural part of the building.


A subordinate space between an entrance and the main interior.

Frost Line

The greatest depth to which ground material may be expected to freeze. The frost line varies by geographic location.



Functional Performance Testing (FPT)

The process of determining the ability of the commissioned systems to perform in accordance with the owner’s project requirements, basis of design, and construction documents.

Gable Roof

A ridged roof that terminates either at one end or both ends in a gable. The end of a ridged roof that, at its extremity, is not returned on itself but is cut off in a vertical plane which above the eaves is triangular in shape due to the slope of the roof.

Gambrel Roof

A type of roof that has its slope broken by an obtuse angle, so that the lower slope is steeper than the upper slope; a roof with two pitches.

Glass (Obscure)

Sheet glass that has been made translucent instead of transparent. It is sandblasted or molded to make the surfaces irregular.

Glass (Wire)

Glass in which wire mesh is embedded to prevent shattering.


The general term applied to material installed in openings such as windows and normally used in reference to glass.

Glazing Factor

The ratio of interior illuminance at a given point on a given plan (usually the work plan) to the exterior illuminance under known overcast sky conditions. LEED uses a simplified approach for its credit compliance calculations.  The variables used to determine the daylight factor include the floor area, window area, window geometry, visible transmittance, and window height.

Grab Bar

A short length of metal or plastic bar attached to a wall in a bathroom, near a toilet, in a shower, or above a bathtub.


1. The slope of a road, channel, or natural ground.

2. The ground level around a building.

Grade Beam

A horizontal load-bearing foundation member that forms a foundation.

Gravel Roof

A roof made waterproof with roofing felt, sealed or bonded, and covered with a layer of gravel to improve its insulation value and protect it from the sun.

Gray water (also spelled grey water)

Defined by the Uniform Plumbing Code (UPC) in its Appendix G, titled “Gray water Systems for Single-Family Dwellings,” as “untreated household wastewater which has not come into contact with toilet waste.  Grey water includes used water from bathtubs, showers, bathroom washbasins, and water from clothes-washer and laundry tubs.  It shall not include wastewater from kitchen sinks or dishwashers.”

Greenhouse Gases

Gases such as carbon dioxide, methane, and CFC’s, that are relatively transparent to the higher-energy sunlight, but trap lower-energy infrared radiation.


A mixture of cementitious material aggregates to which sufficient water has been added to produce pouring consistency without segregation of the constituents.


A shallow channel or conduit of metal or wood set below the roof plane and along the eaves of a house to catch and carry rainwater.

Gypsum Plasterboard

A common building material made with a core of gypsum or anhydrite plaster usually enclosed between two sheets of heavy paper. Primarily used for sheeting interior walls.


Substances used in fire suppression systems and fire extinguishers in buildings.  These substances deplete the stratospheric ozone layer.

Handicap Water Cooler

A water cooler set low and operated by push-bars or levers for convenience to persons with physical impairment.


Persons who are limited from using the physical environment because of physical or mental limitations.


Wood fibers and a bonding agent joined together under pressure to form a sheet of material.

Heat Island Effect

Occurs when warmer temperatures are experienced in urban landscapes compared to adjacent rural areas as a result of solar energy retention on constructed surfaces.  Principal surfaces that contribute to the heat island effect include streets, sidewalks, parking lots, and buildings.

Heat Pump

A refrigerating system employed to transfer heat into or out of a space. The condenser provides the heat while the evaporator is arranged to pick up heat from the air, water, etc. By shifting the flow of air or other fluid, a heat pump system may also be used to cool the space.

Heat Pump-Cooling and Heating

A refrigerating system designed so that the heat extracted at a low temperature and the heat rejected at a higher temperature may be utilized alternately or simultaneously for cooling and heating functions respectively.

High Chair

A chair-shaped device used to hold reinforcing steel off of the bottom of the formwork.

High-Pressure Sodium Lamp

A sodium vapor lamp operating at a partial vapor pressure of 0.1 atmospheres that produces a wide spectrum yellow light.

Hip Roof

A roof that rises by inclined planes from all four sides of a building. The line where two adjacent sloping sides of a roof meet is called the hip.

Hollow-Core Door

A flush door in which plywood or hardwood for both faces is glued to a skeleton framework. It is lighter and less expensive than a solid door.

Hollow Metal Door

A hollow-core door constructed of channel-reinforced sheet metal usually 18 gauge. The core may be filled with some type of lightweight material.

Hooked Bar

A reinforcing bar with the end bent into a hook to provide anchorage.

Horizontal View at 42 Inches

The approach used to confirm that the direct line of sight to perimeter vision glazing remains available from a seated position.  It uses section drawings that include the installed furniture to make the determination.

HVAC Systems

Include heating, ventilating, and air-conditioning systems used to provide thermal comfort and ventilation for building interiors.

Hydrochlorofluorocarbons (HCFC’s)

Refrigerants used in building equipment that deplete the stratospheric ozone layer, but to a lesser extent than CFCs.

Hydrofluorocarbons (HFC’s)

Refrigerants that do not deplete the stratospheric ozone layer.  However, some HFCs have high global warming potential and, thus, are not environmentally benign.

Impervious Surfaces

Surfaces that promote runoff of precipitation volumes instead of infiltration into the subsurface.  The imperviousness or degree of runoff potential can be estimated for different surface materials.

Incandescent Lighting

A light source consisting of a glass bulb containing a filament in a vacuum that may be kept incandescent by the transmission of electric current.

Indoor Adhesive, Sealant, and/or Sealant Primer Product

Defined as an adhesive or sealant product applied on-site, inside of the building’s weatherproofing system.

Indoor Air Quality

The nature of air inside the space that affects the health and well-being of building occupants.

Indoor Carpet Systems

Defined as carpet, carpet adhesive, or carpet cushion product installed on-site, inside of the building’s weatherproofing system.


Uncontrolled inward air leakage to conditioned spaces through unintentional openings in ceilings, floors, and walls from unconditioned spaces or the outdoors caused by the same pressure differences that induce exfiltration.

Inlaid Parquet

Parquet flooring fixed in blocks in varying sizes to a wood backing and then attached to floorboards.

Installation Inspection

The process of inspecting components of the commissioned systems to determine if they are installed properly and ready for systems performance testing.

Interior Lighting Power Allowance

The maximum light power in watts allowed for the interior of a building.

Invasive Plants

Both indigenous and non-indigenous species or strains that are characteristically adaptable, aggressive, have a high reproductive capacity, and tend to overrun the ecosystems in which they inhabit.  Collectively they are one of the great threats to biodiversity and ecosystem stability.


Window blinds or shutters with fixes or movable horizontal slats of wood, metal or glass sloping upward from the outside to admit light and air serving to exclude rain, water and sunlight; somewhat like a Venetian blind.


Derived from fibrous plant native to India and the Far East. It is shredded and spun into yarn that may be used as the backing yarn for woven carpets, or woven into a backing fabric for tufted carpets.

Laminate Adhesive

An adhesive used in wood/agrifiber products (veneered panels, composite wood products contained in engineered lumber, door assemblies, etc.)

Laminated Fiber Wallboard

Fiberboard made in thin layers cemented together. It is used for paneling walls, ceilings, etc., and is made with a surface that is smooth, pebbled, painted, or prepared for painting.

Laminated Wood

A piece of wood built up of laminations that have been joined either with glue or mechanical fastenings.

Lap Siding (Clapboard)

The finish siding on the exterior of a building. A long thin board with one edge thicker than the other; used as siding by lapping one board over the board below.


A bathroom sink.

Legal Description

A detailed description of the exact location of a property.

Life Cycle Analysis (LCA)

An evaluation of the environmental effects of a product or activity holistically, by analyzing the entire life cycle of a particular material, process, product, technology, service, or activity.

Life Cycle Cost (LCC) Method

A technique of economic evaluation that sums over a given study period the costs of initial investment (less resale value), replacements, operations (including energy use), and maintenance and repair of an investment decision (express in present or annual value terms).

Light Pollution

Waste light from building sites that produces glare is directed upward to the sky or is directed off the site.

Lighting Outlet

Connection to a branch circuit, made in a protective box, to which a light fixture or lamp holder is directly attached or from which wires are extended to fixtures.

Load-Bearing Wall

Any wall that bears its own weight and the transferred load of other adjacent structural systems; part of the load path in a structural system.

Local Zoning Requirements

Local government regulations imposed to promote the orderly development of private lands and to prevent land-use conflicts.


A complete system including all the mechanical parts and accessories of a lock, such as knobs, reinforcing plates, and protective escutcheons.

Louvered Blind

Adjustable louvers on blinds to control the amount of shade or sunlight entering windows.

Main Disconnect

A mechanical means of completely shutting off electrical service to the entire building.

Makeup Air

Any combination of outdoor and transfer air intended to replace exhaust air and exfiltration.


A decorative façade, usually highly pitched frame attached at the eave line of a building.

Mansard Roof

A roof with two slopes or pitches on each of the four sides, the lower slopes steeper than the upper.


A brand name for a hardboard product having a variety of uses such as roofing, siding, paneling, and door skins.

Mast-Weather Head

An exterior vertical raceway extending above the roof with electrical feeder conductors installed from the local power distributor.

Mating Beam

The beam on top of the mating wall for support of the roof system, or the beam in the floor system for mating of the two floors.

Mechanical Ventilation

Ventilation provided by mechanical powered equipment, such as motor-driven fans and blowers, but not by devices such as wind-driven turbine ventilators and mechanically operated windows.

Metal Clad Fire Door

A flush door with a wood core or a heat-insulating material covered with sheet metal.

Metal Gutters

A type of attached gutter prefabricated of sheet metal.

Metering Controls

Generally manual on/automatic off controls which are used to limit the flow time of water.  These types of controls are most commonly installed on lavatory faucets and on showers.


Involves irrigation systems with small sprinklers and micro-jets or drippers designed to apply small volumes of water.  The sprinklers and micro-jets are installed within a few centimeters of the ground, while drippers are laid on or below grade.

Mixed-mode Ventilation

A ventilation strategy that combines natural ventilation with mechanical ventilation, allowing the building to be ventilated either mechanically or naturally; and at times both mechanically and naturally simultaneously.


An ornamental strip of material used at joints, cornices, bases, door and window trim, and most commonly made of wood, plaster, plastic, or metal.

Mono-Pitch Truss

An assembly of lumber with a horizontal bottom chord and a pitched top cord, separated by diagonal web members and slopes to one side only.

Mop Sink

A low, deep sink used for janitors.


A mixture of cement, sand, lime, and water used in masonry construction. Used in binding CMUs together.

Narrow Light Door

A door with a narrow vertical window near the lock stile.

Native (Indigenous Plants)

Plants that have adapted to a given area during a defined time period and are not invasive.  In America, the term often refers to plants growing in a region prior to the time of settlement by people of European descent.

Natural Ventilation

Ventilation provided by thermal, wind, or diffusion effects through doors, windows, or other intentional openings in the building.

Net Metering

A metering and billing arrangement that allows on-site generators to send excess electricity flows to the regional power grid.  These electricity flows offset a portion of the electricity flows drawn from the rid.

Non-bearing Wall

A wall that merely separates space into rooms but does not carry overhead partitions or floor joist loads.

Non-occupied Spaces

Include all rooms used by maintenance personnel that are not open for use by occupants.  Included in this category are janitorial, storage and equipment rooms, and closets.

Non-potable Water

Water that is not suitable for human consumption without treatment that meets or exceeds EPA drinking water standards.

Non-regularly Occupied Spaces

Includes corridors, hallways, lobbies, break rooms, copy rooms, storage rooms, kitchens, restrooms, stairwells, etc.

Non-roof Impervious Surfaces

Includes all surfaces on the site with a perviousness of less than 50%, not including the roof of the building.  Examples of typically impervious surfaces include parking lots, roads, sidewalks, and plazas.

Non-water-using Urinal

A urinal that uses no water, but instead replaces the water flush with a specially designed trap that containers a layer of buoyant liquid that floats above the urine layer, blocking sewer gas and urine odors from the room.

Nylon Fiber

A thermoplastic polyamide resin derived from coal tar base, air, and water.

Odd-Pitch Roof

A roof on which the rise is not an even fraction of the run also called a low slope.


The emission of volatile organic compounds from synthetic and natural products.

On-site Wastewater Treatment

Uses localized treatment systems to transport, store, treat and dispose of wastewater volumes generated on the project site.

Open Space Area

Open Space Area is as defined by local zoning requirements.  If local zoning requirements do not clearly define open space, it is defined for the purposes of LEED calculations as the property area minus the development footprint; and it must be vegetated and pervious, with exceptions only as noted in the credit requirements section.  For projects located in urban areas that earn SS Credit 2, open space also includes non-vehicular, pedestrian-oriented hardscape spaces.

Open-grid Pavement

Defined for LEED purposes as pavement that is less than 50% impervious and contains vegetation in the open cells.

Operable Window

A window that may be opened and shut to accommodate ventilation needs, as opposed to a fixed light or fixed sash.


Occupational Safety and Health Administration (or Act, depending on its usage)

Outdoor Air

The ambient air that enters a building through a ventilation system, through intentional openings for natural ventilation, or by infiltration.

Outdoor Lighting Zone Definitions

Developed by IDA for the Model Lighting Ordinance, these definitions provide a general description of the site environment/context and basic site lighting criteria.


The projected area of a roof or upper story beyond the plane of the lower wall.

Owner’s Project Requirements (OPR)

An explanation of the ideas, concepts, and criteria that are determined by the owner to be important to the success of the project (previously called the Design Intent).

Packaged Air Conditioner

A factory-assembled air conditioning unit ready for installation. The unit may be mounted in a window, an opening through a wall, or on the building roof. These units may serve an individual room, a zone, or multiple zones.

Panel Box

The electrical box located on the wall where the incoming electrical service is connected and then distributed throughout the building.

Paneled Door

A door that consists of raised or indented panels. Also referred to as a “colonial door”.

Panic Hardware

A door locking assembly that can be released quickly by pressure on a horizontal bar.

Parabolic Reflector

A reflector shaped to focus light in a controlled beam.


A protective low wall along the edge of a roof. That portion of any wall that extends above the roofline.

Particle Board

A composition board consisting of distinct particles of wood bonded together with a synthetic resin or other added binder.


Interior walls used to define or create spaces such as rooms, closets, etc. Normally non-load bearing.

Peaked Roof

A roof rising either to a point or ridge.

Pent Roof

A roof with a slope on one side only. Also called a shed roof.

Percentage Improvement

The percent energy costs savings for the Proposed Building Performance versus the Baseline Building Performance.


Perforated paper joint tape approximately two inches wide; used to cover the joints in gypsum wallboard.


Governmental approval for various types of construction on a site to begin.


The percent of the surface area of a paving material that is open and allows moisture to pass through the material and soak into the earth below the paving system.


A solid support of masonry construction

Pile Height

The height of piles in a rug measured from the top surface of the backing to the top of the pile.

Pitched Roof

The most common type of roof, usually with slopes of more than 2 in 12 vertical to horizontal.


Chamber or space forming a part of an air-conditioning system. A chamber into which air is blown for distribution through ducts.

Plot Plan

Drawing that shows the location of buildings, structures, utilities, parking, and landscaping.   Also called “Site Plan”.


A fabricated wood product constructed of three or more layers of veneer joined with glue, usually laid with grain of adjoining piles at right angles.


Waste material generated by households or by commercial, industrial, and institutional facilities in their role as end-users of the product, which can no longer be used for its intended purposes.

Potable Water

Water suitable for drinking and supplied from wells or municipal water systems.

Pre-consumer Content

Defined as material diverted from the waste stream during the manufacturing process.

Pre-Hung Door

A packaged unit consisting of a finished door mounted in a frame.


A measure of a construction materials’ ability to retard the flow of heat. The rating of insulation material. The higher the R-value, the higher the ability to insulate.

Raised Roof

Abrupt transition of a roof from a given height to an increased height.

Rapidly Renewable Materials

Material considered to be an agricultural product, both fiber, and animal, that takes 10 years or less to grow or raise, and to harvest in an ongoing and sustainable fashion.

Receptacle Load

Refers to all equipment that is plugged into the electrical system, from office equipment to refrigerators.

Ready-Mixed Concrete

Concrete manufactured for delivery to a project site in a plastic and unhardened state.

Recessed Lighting Fixture

A lamp fixture that has its bottom edge flush with the ceiling.

Recirculated Air

The air removed from a space and reused as supply air.


The collection, reprocessing, marketing, and use of materials that were diverted or recovered from the solid waste stream.


The working fluids of refrigeration cycles.  Refrigerants absorb heat from a reservoir at low temperatures and reject heat at higher temperatures.

Regionally Extracted Materials

For LEED for New Construction purposes must have their source as a raw material from within a 500-mile radius of the project site.

Regionally Manufactured Materials

For LEED for New Construction purposes must be assembled as a finished product within a 500-mile radius of the project site.  Assembly, as used for this LEED definition, does not include on-site assembly, erection, or installation of finished components, as in structural steel, miscellaneous iron, or systems furniture.


The appliance at the end of a duct for incoming or escaping air sometimes used to direct airflow or control the volume of air passing through it.

Regularly Occupied Spaces

Areas where workers are seated or standing as they work inside a building; in residential applications, it refers to living and family rooms.

Relative Humidity

The ratio of partial density of water vapor in the air to the saturation density of water vapor at the same temperature and the same total pressure.


The process of cleaning up a contaminated site by physical, chemical, or biological means.  Remediation processes are typically applied to contaminated soil and groundwater.

Renewable Energy Certificates (RECs)

RECs are a representation of the environmental attributes of green power and are sold separately from the electrons that make up the electricity.  RECs allow the purchase of green power even when the electrons are not purchased.

Return Air

The air removed from a space to then be recirculated or exhausted.

Return Air Duct

Ducts through which the cold air or return air passes on its way back to the heating or cooling unit.


A strategy to return materials to active use in the same or a related capacity.

Ribbon Footing (Grade Beam/Strip Footing)

A narrow strip of concrete upon which walls are constructed.


The highest point on the roof or the highest point where more than one roof plane comes together.

Ridge Cap

The finishing touch on a gable roof system. It can be made of composition roofing or metal and extends the length of the building, folding over the two sides of the ridge.

Ridge Vent

Located at the ridge of a roof system. It is sheet metal or plastic configuration designed to allow the air within the roof system to vent.

Risk Management

A methodology used to analyze for potential health effects caused by contaminants in the environment.  Information from the risk assessment is used to determine cleanup levels.

Roofing tiles

Steel, concrete, burnt clay, or asbestos-cement tiles for covering roofs. Tiles are of three general types: (a) plain tiles, (b) shingle-lap tiles, (c) Italian tiling or Spanish tiling.

Roof Overhang

A roof extension beyond the end wall/sidewall of a building.

Roof Pitch

The slope of a roof expressed as the ratio of the rise of the roof to the horizontal span. The angle that a roof surface makes with the horizontal. Usually expressed as the units of a vertical rise to 12 units of horizontal run.

Roof Ventilation

Available through gable vents, ridge vents, or soffit vents; the act of allowing air to circulate within the roof or attic area.

Room Air Conditioner

A factory-encased air conditioner designed as a self-contained unit for mounting in a window, through a wall, or as a console. It is designed for the delivery of conditioned air to an enclosed space without ducts.

Safety Glass

A laminate consisting of two or more sheets of float glass, usually plate or sheet, with an intermediate layer of transparent plastic bonded together by heat and pressure

Salvaged Materials

Construction materials recovered from existing buildings or construction sites and reused in other buildings.  Common salvaged materials include structural beams and posts, flooring, doors, cabinetry, brick, and decorative items.


The framework that holds the glass in a window or door.


Any material with adhesive properties that is formulated primarily to fill, seal, or water-proof gaps or joints between two surfaces.  Sealants include sealant primers and caulks.


The addition of soils to water bodies by natural and human-related activities.  Sedimentation decreases water quality and accelerates the aging process of lakes, rivers, and streams.

Service Box

Within a building a metal box located at the point where the electric service conductors enter the building. The spot in the building where the electricity is brought into the building from the local power distribution center.

Service (Entrance) Equipment

Assembly or switches and switch-like devices which permit disconnecting all power, distributing it to various branch circuits through overcurrent devices such as fuses or circuit breakers. Assembly of fuses or circuit breakers, with or without a disconnection means, also is termed a distribution panel or panel board.

Service Panel

Same as the panel box or panel board.


A hand-split wood shingle.

Shared (Group) Multi-occupant Spaces

Includes conference rooms, classrooms, and other indoor spaces used as a place of congregation for presentations, training, etc.  Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with an accessible thermostat and air-flow control.

Shed Roof

A roof having a single sloping plane.


(1) Roof or wall covering of asphalt, asbestos, wood, tile, slate, or another material cut into stock lengths, widths, and thicknesses. (2) A wedge-shaped piece of wood or other material used in overlapping courses to cover a roof or an outside wall surface.

Shingle Tile

A flat clay tile used for roofing.

Shop Sink

A deep sink set low on a wall used to clean mops and to empty and clean pails.

Shower Stall

The compartment and plumbing provided for bathing utilizing an overhead spray.

Side Light

One or a pair of narrow windows flanking a door.


Any type of exterior finish applied to the exterior wall.

Siding Shingles

Relatively small individual siding units that overlap each other to provide weather protection. They typically are applied to a nailing base, such as sheathing or horizontal nailing strips, which support the shingles between structural framing members.

Single-Pitch Roof

A lean-to roof. It slopes in only one direction also called a shed roof.


A plumbing fixture consisting of a water supply, a basin, and a drain connection.

Site Assessment

An evaluation of above ground (including facilities) and subsurface characteristics, including the geology and hydrology of the site, to determine if a release has occurred, as well as the extent and concentration of the release. The information generated during a site assessment is used to support remedial action decisions.

Skirt Board (Skirting)

A lower wall extension installed to enclose the underside of a temporary building that spans from the floor framing to the ground.

Sliding Slash

Any window that moves horizontally in grooves.

Solid Core Door

(1) A flush door with a solid core. (2) A fire-resisting door built with three thicknesses of tongued and grooved boarding, the inner one horizontal, and the other ones vertical. Sometimes such a door is plated with sheet metal.

Soffit Vent

A perforated or louvered material attached to the tail of the truss and the sidewall to allow air movement within the truss system.

Solid Glass Door

A door in which the glass essentially provides all the structural strength.

Sonotube (trade name)

A circular pre-formed casing made of laminated paper used for forming cylindrical columns, piers, or stems.

Sound Rated Door

A door constructed to provide greater sound attenuation than that provided by a normal door, usually rated in terms of its sound transmission class (STC).

Special-Purpose Outlet

Point of connection to the electrical system for a particular piece of equipment normally reserved for the exclusive use of the equipment sometimes called a dedicated circuit.

Sprinkler System

An arrangement of overhead pipes equipped with sprinkler heads or nozzles. In case of fire, these nozzles automatically release sprays of water.

Square Footage

The total area in square feet of all rooms of a building, including corridors, elevators, stairwells, and shaft spaces.

Stable Door (Dutch Door)

A door cut through horizontally at about half its height with each half hung separately.


Color in a dissolving vehicle. When spread on an absorptive surface, it penetrates and gives its color to the wood or other material.

Standing Seam

This type of roofing is available in several variations of the seaming method. It makes the most watertight sheet roofing, and it should be used on roof slopes of less than 3” drop in a 12” run and is effective on slopes as slight as a 2” drop in a 12” run. Seams may be locked, double-locked, soldered, or welded.

Storm Window

An extra window usually placed on the outside of an existing window as additional protection against cold weather.

Stormwater Run-off

Water volumes that are created during precipitation events and that flow over surfaces into sewer systems or receiving waters.  All precipitation waters that leave project site boundaries on the surface are considered to be stormwater run-off volumes.

Strip Lighting

A lighting assembly used to flood all or part of an area, consisting of a row of single lamps mounted in a trough with a reflecting hood.


Portland cement, water, sand, and possibly a small quantity of lime (Portland cement plaster), along with, perhaps, other aggregates used on exterior surfaces.

Supply Air

The air delivered by mechanical or natural ventilation to space, composed of any combination of outdoor air, recirculated air, or transfer air.

Suspended Ceiling

Normally hung from the bottom chord of the truss or ceiling with wires, consisting of T-grid supports. The pattern is normally 2’x4’ with gypsum or mineral board acoustical ceiling tiles.

Sustainable Forestry

The practice of managing forest resources to meet the long-term forest product needs of humans while maintaining the biodiversity of forested landscapes.  The primary goal is to restore, enhance and sustain a full range of forest values – economic, social, and ecological.

Switch Pate

A flush plate used to cover an electric switch.

System Performance Testing

The process of determining the ability of the commissioned systems to perform in accordance with the owner’s project requirements, basis of design, and construction documents.


A registered trade name of the American Plywood Association for siding panels with special surface treatment, such as saw textured, and having grooves spaced regularly across the face.

Thermal Comfort

A condition of mind experienced by building occupants expressing satisfaction with the thermal environment.

Tinted Glass

Made by a special process that involves the inclusion of certain admixtures to the glass batch. The result is a glass with the capacity for significantly lowering the transmission of solar heat through the glass in the building. At the same time, the transmission of visible light is reduced to a degree that depends upon the particular tint and thickness of glass.

Tipping Fees

Fees charged by a landfill for disposal of waste volumes.  The fee is typically quoted for one ton of waste.

Toilet Partition

One of the panels forming a toilet enclosure.

Tongue and Groove

Sheeting, usually wood, in which one edge of the sheet is cut with a projecting tongue that fits into the corresponding groove or recess in the edge of the next sheet.

Top Hung Window

A window hinged from the top also called an awning style.


At right angles to the longitudinal axis of the building.

Undercut Doors

The action or result of cutting away the bottom of the door. A door with greater than normal clearance on the floor to give more ventilation to an area.

Veneered Wall

A thick sheet of wood, single facing of masonry units or similar materials securely attached to a wall for the purpose of providing ornamentation, protection, or insulation, but not bonded or attached to intentionally exert common action under load.

Venetian blind

A screen for doors or windows formed of horizontal slats supported on vertical strips of webbing. It is capable of being collapsed into a small space when raised, and the slats are movable to admit or exclude light.


The process of supplying air to or removing air from a space for the purpose of controlling air contaminant levels, humidity, or temperature within the space.


The full range of checks and tests carried out to determine if all components, subsystems, systems, and interfaces between systems operate in accordance with the contract documents. In this context, “operate” includes all modes and sequences of control operation, interlocks, and conditional control responses, and specified responses to abnormal or emergency conditions.

Vertical Siding

A type of exterior cladding consisting of side-matched boards.

Vertical Sliding Window

A window with one or more sashes that move only in a vertical direction; also called single and double-hung depending on how many sash sections are operable.

VOCs (Volatile Organic Compounds)

Carbon compounds that participate in atmospheric photochemical reactions (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides and carbonates, and ammonium carbonate).  The compounds vaporize (become a gas) at normal room temperatures.

Wall-Hung Water Closet

A water closet mounted on a wall so the area beneath is clear for cleaning.


A special paper, plain or printed, for pasting upon a smooth interior wall surface as decoration.

Water Closet

A plumbing fixture used to receive human waste and then allow for flushing to a waste pipe. Also called a “toilet”.

Wood Molding

Wood strips factory-shaped in commercially available patterns.