| Term | Definition |
| d | See Penny. |
| D Cracking | The progressive formation on a concrete surface of a series of fine cracks at rather close intervals, often of random patterns, but in slabs on grade paralleling edges, joints, and cracks and usually curving across slab corners; also called D-Cracks and D |
| D Line Cracks | See D Cracking. |
| D Load | A constant load that in structures is due to the mass of the members, the supported structure, and permanent attachments or accessories. |
| D&M | Dressed and Matched. |
| Dado | A groove cut into a board or panel intended to receive the edge of a connecting board or panel; Lower part of interior wall, beneath dado-rail. |
| Dado Joint | A joint in which one piece is grooved to receive the piece which forms the other part of the joint. |
| dado-rail | Molding dividing lower part of wall (dado) from upper (infill). Originally designed to stop chair backs from damaging wall decoration, it is known as a chair rail in the United States. |
| Dairy | A building or room for the storage, processing, or sales of milk and milk products. |
| Dalton’s Law | Vapor pressure created in a container by a mixture of gases is equal to the sum of individual vapor pressures of the gases contained in mixture. |
| Damages | 1. Injuries. 2. An amount of money awarded to a plaintiff to compensate for loss caused by the wrongful conduct of a defendant. |
| damask | Was traditionally made from silk from Damascus but is distinguished by the weave rather than the fiber content and can also be made in silk, cotton, linen, wool or man-made fibers. Its durability depends on its fiber content, so it should be chosen accord |
| Dammar | A natural resin used extensively in the preparation of varnishes and lacquers; usually classified according to the place from which it is shipped to market, for example, Singapore dammar or Batavia dammar. |
| Damp Check | See Damp Course. |
| Damp Course | A course or layer of impervious material which prevents capillary entrance of moisture from the ground or a lower course; also called Damp Check. |
| Damp Location | A location subject to a moderate degree of moisture, such as some basements, some barns, some cold storage warehouses, and the like. |
| Damper | A flap to control or obstruct the flow of air or other gasses; specifically, a metal control flap in the throat of a fireplace, or in an air duct; controls that vary airflow through an air outlet, inlet, or duct; a damper position may be immovable, manual |
| Damping | 1. Dissipation of structure-borne noise by conversion to some other form of energy, usually heat; usually accomplished by using a material with a high internal energy-absorbing capacity. 2. A rate at which natural vibration decays as a result of absorptio |
| Dampproofing | The treatment of concrete or mortar to help prevent the passage or absorption of water in the absence of hydrostatic pressure; not necessarily waterproof. |
| Dap | To cut and form a recess in timber to form a dapped joint; also called a let-in joint, as where 1" x 6" diagonal bracing is cut into 2" x 4" studs. |
| Darby | 1. A hand-manipulated straightedge, usually 3 to 8 feet. (1 to 2.5 m) long, used in the leveling operation of the early stage of concrete placement, preceding supplemental floating and finishing. 2. A stiff straightedge, about 4 inches wide and 42 inches |
| Darkroom | A room for photographic work, with normal light excluded. |
| Darkroom Dryer | A mechanical drying device used by a photographer in a darkroom to dry prints. |
| Darkroom Equipment | Equipment used for the developing of photographs. |
| Darkroom Sink | A basin in a photographic darkroom for the dispensing or holding of liquids. |
| Dash Bond Coat | A thick slurry of portland cement, sand, and water flicked on surfaces with a paddle or brush to provide a base for subsequent portland cement plaster coats; sometimes used as a final finish on plaster. |
| Dash Brush | A long-bristled brush for flinging a plaster mixture on the wall as a dash coat. |
| Datum | 1. The fixed starting point for surveying or measuring. 2. A piece of information. |
| Daub | A glob of adhesive. |
| Daylight | A painting defect where there is a lack of coverage of a coat of paint; The end of a pipe (the terminal end) that is not attached to anything. |
| Daylighting | Illuminating the interior of a building by natural means. |
| Days | Calendar days are consecutive days on the calendar; working days are calendar days less non-working days such as week ends and holidays. |
| db | Decibel. |
| DB | Dry Bulb. |
| DBA | Doing Business As. |
| DBIA | Design/Build Institute of America. |
| Dbl Conduit | Double thick conduit. |
| Dbl Duct | Double thick metal duct. |
| DC | Direct Current. |
| DE | Diatomaceous Earth. |
| De Facto | In reality; actually; in fact, whether by right or not. |
| De Jure | By right or of right. |
| De-humidistat | A control mechanism used to operate a mechanical ventilation system based upon the relative humidity in the home. |
| De-light | Term used by Hunter Douglas to describe the option of making a blind without rout holes. |
| Dead bolt | An exterior security lock installed on exterior entry doors that can be activated only with a key or thumb-turn. Unlike a latch, which has a beveled tongue, dead bolts have square ends. |
| Dead Burned | Removal of all water content during calcining of gypsum. |
| Dead End | A branch leading from a soil, waste or vent pipe, building drain sewer which is terminated at a developed length of 2 feet or more by means of a plug or other fitting. A dead end is not used to admit water or air into the piping system. |
| Dead Flat | In paint, having no gloss at all. |
| Dead Knot | Loose knot in wood, usually dark in color. |
| Dead Level | An absolutely horizontal roof. slope. |
| Dead Level Asphalt | A roofing asphalt that has a softening point of 140° F (60° C). |
| Dead light | The fixed, non-operable window section of a window unit. |
| Dead Load | The load due to the vertical weight of all permanent structural and nonstructural elements of a building, such as walls, floors, and roofs. |
| Dead Man's Switch | One that stays in on or off position only as long as it is held there manually. |
| Dead Space | 1. A space with an abundance of absorptive surfaces that does not support sound. 2. A space between walls or a floor and ceiling. |
| Dead-Front | As applied to switches, circuit breakers, switchboards, control panels, and panelboards, so designed, constructed, and installed that no current-carrying parts are normally exposed on the front. |
| Deadening | Construction intended to prevent the passage of sound. |
| deadlight | Space immediately above the window architrave and below the ceiling and cornice. |
| Deadlock | A lock equipped with a deadbolt only. |
| Deadman | A log or block of concrete, or other material buried in a streambank that is used to tie in a revetment with cable, chain, or steel rods. |
| Deaeration | Act of separating air from substances. |
| Deal | Softwood timber. |
| Debris | Accumulated rubbish, trash and fragments of waste. |
| Debt | Money that is owed. |
| Debt, Long Term | See Long Term Debt. |
| Debt, Short Term | See Short Term Debt. |
| Debtors | Persons or companies that owe money to the business; accounts or notes receivable. |
| Decal | Decalcomania. |
| Decalcomania | Pictures,diagrams and designs, on specially prepared paper, that can be transferred to glass or other surfaces; also called a Decal. |
| Decay | Disintegration of wood or other substance through the action of fungi. |
| Dechlorination | The removal of chlorine from water. |
| Decibel (db) | A standard unit of measure for classifying the transmission of airborne sound levels; the ratio of sound pressure to a base level chosen at the threshold of hearing and ranging up to 130 for the average pain level. |
| Deciduous | Trees which annually lose their leaves. |
| Decimal | Any real number expressed in base 10. |
| Decimal Fraction | A fraction or mixed number in which the denominator is a power of 10, usually expressed by use of the decimal point, as 1/4 = 25/100 = 0.25. |
| Deck | 1. The roof surface to be covered, the substrate or substrata. 2. A small platform used for walking. 3. The form on which concrete for a slab is placed. 4. A floor or roof slab. |
| Deck Insulation | Thin sheets of insulation placed on a concrete surface before a flooring system is installed. |
| Deck Level Pool | Water surface level with the deck. |
| Deck Mud | See Floor Mud. |
| Deck Paint | An enamel with a high degree of resistance to mechanical wear; designed for use on such surfaces as porch floors. |
| Deck, Coil | See Coil Deck. |
| Deck, decked | To install the plywood or wafer board sheeting on the floor joists, rafters, or trusses. |
| Decking, Cellular | See Cellular Decking. |
| Decking, Metal | See Metal Decking. |
| Decking, Open | See Open Decking. |
| Decking, Wood | See Wood Decking. |
| Declaration of Homestead | See Homestead, 3. |
| Declining Balance | A form of accelerated depreciation where a larger amount is taken in the beginning years gradually declining to a smaller amount in the later years. |
| Decor | The furnishing, layout, style, and decoration of building interiors. |
| Decor blind | 8 gauge aluminum blind manufactured by Hunter Douglas. |
| Decorated | Adorned, embellished, or made more attractive by means of color or surface detail. |
| Decoration | 1. The act of decorating. 2. The finish used over the gypsumboard face. |
| Decoration, Inglaze | See Inglaze Decoration. |
| Decoration, Overglaze | See Overglaze Decoration. |
| Decoration, Underglaze | See Underglaze Decoration. |
| Decorative Painting | Architectural painting; aesthetic painting. |
| Decorative Tile | Tile with a ceramic decoration on the surface. |
| decorator tape | Tape that is stitched to the top of a curtain to create a feathered heading or pinch pleats either by pulling cords running through the tape or by inserting special pleater hooks. |
| Decoupling | Separating elements to retard the transmission of structural-borne sound, thermal conductance, or physical loads. |
| Dedicated circuit | An electrical circuit that serves only one appliance (ie, dishwasher) or a series of electric heaters or smoke detectors. |
| Dedication | The appropriation of land or easements by a private owner for public purposes or use. |
| Deductive Alternate | An alternate bid that, if accepted, reduces the contract price. |
| Deed of Trust | See Trust Deed. |
| Deed Restrictions | Restrictive covenants often included in a deed which may limit future uses of the land, and other restrictions such as height, size, and aesthetics, as long as they are not against the public interest. |
| Deeds | A general term which refers to all documents conveying property, from one person to another. |
| Deep Color | Intense or strong color with no apparent presence of black. |
| Deep Seal-P Trap | A P-trap with a water seal depth of more than 4 inches. |
| Deep Strength Asphalt Pavement | A pavement structure in which the wearing course and a substantial portion of the base consist of asphalt. |
| Default | A material failure to perform the requirements of a contract. |
| Defect | An imperfection. |
| Defendant | A party against whom a legal claim is made in a civil law suit. |
| Deferred Maintenance | Repair and upkeep that has been neglected or postponed. |
| Deficit | An economic shortfall, where expenses exceed income; a debit balance in the retained earnings account. |
| Deflection | 1. A variation in position or shape of a structure or structural element due to effects of loads or volume change, usually measured as a linear deviation from an established plane rather than an angular variation. 2. Displacement or bending of a structura |
| Deformation | The change in shape of a body brought about by the application of a force. Deformation is proportional to the force within the elastic limits of the material. |
| Deformation, Eutectic | See Eutectic Deformation. |
| Deformed Bar | A steel reinforcing bar manufactured with deformations (bumps, lugs, or ridges) to provide a locking anchorage with the surrounding concrete. |
| Deformed Reinforcement | Deformed reinforcing bars, bar and rod mats, and deformed wire fabric. |
| Defrost Device | Refrigerating cycle in which evaporator frost and ice accumulation is melted. |
| Defrost Timer | Device connected into electrical circuit which shuts unit off long enough to permit ice and frost accumulation on evaporator to melt. |
| Defrosting | Process of removing frost accumulation from evaporators. |
| Defrosting Control | Device to automatically defrost evaporator; it may operate by means of a clock, door cycling mechanism, or during off portion of refrigerating cycle. |
| Defrosting Type Evaporator | Evaporator operating at such temperatures that ice and frost on surface melts during off part of operating cycle. |
| Degradation | A decline in quality; degeneration. |
| Degreaser | Chemical solution for grease removal. |
| Degreasing | Solution or solvent used to remove oil or grease from refrigerator parts. |
| Degree | 1. A unit on one of the temperature scales. 2. A unit of measurement of angles, equal to 60 minutes; a right angle is 90 degrees. |
| Degree Day | Unit that represents one degree of difference from inside temperature and the average outdoor temperature for one day and is often used in estimating fuel requirements for a building. |
| Degree Day Method | A method of computing fuel requirements for HVAC systems, see Degree Day. |
| Degree of Saturation | The amount of water present in the air relative to the maximum amount it can hold at a given temperature without causing condensation. |
| Dehumidification | The removal of moisture from air. |
| Dehumidifier | A machine which removes moisture from the air. |
| Dehydrated Castor Oil | A drying oil prepared from castor oil. |
| Dehydrated Oil | Lubricant which has had most of its water content removed, also called Dry Oil. |
| Dehydration | The process of removing water from a substance. |
| Dehydrator | See Drier, 1. |
| Dehydrator Receiver | Small tank which serves as liquid refrigerant reservoir and which also contains a desiccant to remove moisture; used on most automobile air conditioning installations. |
| Deice Control | Device for operating a refrigerating system in such a way as to provide melting of the accumulated ice and frost. |
| Delamination | 1. Separation of one layer from another. 2. The separation of layers in laminated wood because of failure of the adhesive, either within the adhesive itself or at the interface between the adhesive and the adherend. 3. The failure of a built-up roofing me |
| Delay | Time lost in the construction schedule by any reason. |
| Delicatessen Case | A refrigerated cabinet used for the storing and displaying of perishable foods. |
| Delignification | Removal of part or all of the lignin from wood by chemical treatment. |
| Deliquescence | The natural absorption of atmospheric moisture by a solid substance. |
| Delivery Cart | A heavy or lightweight, two or four-wheeled vehicle used to transport goods. |
| Delivery Tolerances | In asphaltic concrete making, permissible variations from the exact desired proportions of aggregate and bituminous material as delivered into the pugmill. |
| Delmar | Blind and shade fabricator. Division of Newell. Products include Light Guard II, Esprit, Enchante, Softlite Pleated Shades, Touchglide Verticals, and others. |
| Delta | 1. The 4th letter in the Greek alphabet, the capital delta being shaped like an equilateral triangle. 2. Anything so shaped. 3. The alluvial deposit at the mouth of a river. 4. A numbered marking on contract drawings to identify changes. |
| Delta Transformer | Three-phase electrical transformer which has ends of each of three windings electrically connected to form a triangle. |
| Delustered Nylon | Nylon on which the normally high sheen has been reduced by surface treatment. |
| Demand Factor | The demand of any system; the ratio of the maximum demand of the system to the total connected load of the system; the loads of a system are practically never on at the same time due to the many uses of the power; somewhere between the maximum connected l |
| Demand Meter | Instrument which measures the kilowatt-hour usage of a circuit or group of circuits. |
| Demise | Transfer property by will, grant, or lease. |
| Demised Premises | The property leased. |
| Demising Wall | See Party Wall, 3. |
| Demography | The study of the statistics of a human population in respect to trends in size, density, age, and economic characteristics, to identify markets. |
| Demolish | To raze or tear down a building or structure. |
| Demountable Partition | An assembly designed to be dismantled and reassembled with a minimal loss of components. |
| Demur | To take exception; object. |
| Demurrage | A charge for detaining a ship, freight car, or truck during the period of unloading. |
| Demurrer | A response in a court proceeding in which the defendant does not dispute the truth of the allegation but claims it is not sufficient grounds to justify legal action; an objection. |
| Den | A private comfortable room for pursuit of hobbies or recreation. |
| Denatured Alcohol | Grain or ethyl alcohol made unsuitable for beverage purposes by adding compounds of a poisonous nature. |
| Dendriform | Resembling a tree in structure. |
| Dendrochronology | The science of dating events and variations in environment in former periods by comparative study of growth rings in trees and aged wood. |
| Dendroid | Resembling a tree in form. |
| Dendrology | The study of trees. |
| Denier | System of yarn count used for synthetic fibers; the weight in grams per 9,000 meters of yarn length; one denier equals 4,464,528 yards per pound or 279,033 yards per ounce. |
| Dense Graded Mix | An asphalt produced with aggregate that produces a continual grading. Usually low air voids as compared with open graded products. |
| Dense-Graded Aggregate | An aggregate that has a particle size distribution such that when it is compacted, the resulting voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, are relatively small. |
| Densification | The act of increasing the density of a mixture during the compaction process. |
| Density | 1. The quantity per unit volume, unit area, or unit length; in wood it is expressed as pounds per cubic foot, kilograms per cubic meter, or grams per cubic centimeter at a specified moisture content. 2. Closeness of texture or consistency of particles wit |
| Density, Pile Yarn | See Pile Yarn Density. |
| Dental Equipment | Equipment used by dentists for dental work on patients. |
| Dental Light | An adjustable lamp used by dentists, having an arm-like extension enabling it to be maneuvered in any direction, and which focuses light in one direction. |
| Dentil | One of a series of small projecting rectangular blocks forming a molding, part of a cornice. |
| Deodorizer | Device which absorbs or adsorbs various odors, usually by the principle of absorption; activated charcoal is commonly used. |
| Deposit | 1. A natural resource such as iron ore. 2. Settled material, such as sediment. 3. A returnable sum paid usually for safekeeping or to guarantee the return of something. |
| Deposited Metal | Filler metal that has been added during a welding operation. |
| Deposition | 1. The extra-judicial testimony of a witness given under oath. 2. The written record thereof. |
| Depository, Night | See Night Depository. |
| Depreciation | The decrease in value of a property from any cause. |
| Derrick | A hoisting frame with a long beam, ropes, gear, and pulleys that can lift a heavy load and swing it to the side. |
| Desiccant | 1. A drying agent. 2. Substance used to collect and hold moisture in refrigerating system; common desiccants are activated alumina and silica gel. |
| Design | To conceive or plan out in the mind. |
| Design Concept | An architectural idea that is depicted on the drawings and in the specifications with the expectation that it will be faithfully executed by the contractor. |
| Design Development Drawings | Drawings prepared by architects for the Design Development Phase. |
| Design Development Phase | One of the standard phases of architectural service (Schematic Design Phase, Design Development Phase, Construction Documents Phase, Bidding or Negotiation Phase, and Construction Phase-Administration of the Construction Contract). |
| Design Displacement | The design-basis earthquake lateral displacement, excluding additional displacement due to actual and accidental torsion, required for design of the seismic isolation system. |
| Design Filter Rate | See Design Rate of Flow. |
| Design Head | The total head requirement of the circulation system at the design rate of flow. |
| Design Heat Load | The total heat loss from a building under the most severe winter conditions likely to occur. |
| Design Life | The design life of the pavement. The amount of traffic influences the design life. |
| Design Pressure | Highest or most severe pressure expected during operation; sometimes used as the calculated operating pressure plus an allowance for safety. |
| Design Professional | A person educated and skilled in the field of building design or the related structural and environmental systems. |
| Design Rate of Flow | In a pool, spa, or hot tub, the rate of flow in gallons divided by the number of minutes in the turnover time; also called the Design Filter Rate. |
| Design Temperature | A temperature close to the lowest expected for a location, used to determine design heat load. |
| Design/Build | A project delivery system in which the same entity is responsible for both design and construction. |
| Design/Build Institute of America | 1010 Massachusetts Avenue, NW, Suite 350, Washington, DC 20001, (202) 682-0110 |
| Designer Series blind | 8 gauge aluminum miniblind without rout holes. Made by Hunter Douglas. |
| Destructive Distillation | Distilling a product at a temperature so high that products obtained are of different chemical composition than existed in the original material. |
| Destructive Testing | Testing of building materials in a manner that destroys the material. |
| Detail | 1. Extended treatment or attention to particular items. 2. Drawing of a small portion of an assembly. |
| Detectable Warning | A standardized surface or feature built in or applied to walking surfaces or other elements to warn visually impaired persons of hazards in the path of travel. |
| Detector, Leak | See Leak Detector. |
| Detector, Smoke | See Smoke Detector. |
| Detergent | Cleaning agent. |
| Deterioration | Depreciation; loss of value of real property due to physical wear and tear. |
| Determinate | 1. Having defined limits; definite. 2. Statically Determinate; see Statically Determinate Structures. |
| Developed Length | The length as measured along the center line of the pipe and fittings. |
| Development Length | In reinforced concrete, the length of steel reinforcing required to develop the required bond between the reinforcing and the adjacent concrete. |
| Device | 1. A piece of equipment or a mechanism designed for a special purpose or function. 2. An ornamental design. 3. A unit of an electrical system which is intended to carry but not utilize electric energy. |
| Device Cover | A protective or ornamental removable cover over an electrical box or device. |
| Devil’s Float | In plastering, a wooden float with two nails protruding from the toe, used to roughen the surface of the brown coat. |
| Dew | Condensed atmospheric moisture deposited in small drops on cool surfaces. |
| Dew Point | Temperature at which vapor, at 100 percent humidity, begins to condense and deposit as liquid on cold surfaces. |
| Dew-Point Temperature | The temperature at which condensation occurs. |
| Dewatering | To remove water from the ground or excavations with pumps, wellpoints, or drainage systems. |
| Dextral | Right handed. |
| DF | 1. Douglas Fir. 2. Drinking Fountain. |
| DFPA | Douglas Fir Plywood Association |
| DG | Decomposed Granite. |
| DHI | Door & Hardware Institute. |
| Diagnostic Architecture | The science and practice of analyzing building failures to determine the causes and devise repair methods. |
| Diagonal | 1. Running in an oblique direction from a reference line. 2. Inclined member of a truss or bracing system used for stiffening or wind bracing. |
| Diagonal Bond | This is a form of raking bond in which the bricks are laid in an oblique direction in the middle section of a thick wall; the bricks may also be laid in this fashion in paving. |
| Diagonal Bracing | That form of bracing that diagonally connects joints at different levels. |
| Diagonal Sheathing | Wood sheathing with the individual boards running at a 45 degree angle to the studs, joists, or rafters. |
| Diagonal-Grained Wood | 1. Wood in which the annual rings are at an angle with the axis of a piece as a result of sawing at an angle with the bark of the tree or log. 2. A form of cross grain. |
| Diameter | A chord passing through the center of a figure or body, such as a circle. |
| Diamond Mesh | One of the common types of metal lath having a characteristic geometrical pattern produced by the slitting and expansion of metal sheets. |
| Diamond Mesh Window Guard | Guard fabricated of diamond-shaped mesh to provide protection over the face of a window to prevent damage to glass and to prevent intrusion. |
| Diaper | 1. An allover pattern consisting of one or more small repeated units of design, as geometric figures, connecting with one another or growing out of one another with continuously flowing or straight lines. 2. Any repeated and continuous pattern in brickwor |
| Diaphragm | 1.Flexible material usually made of thin metal, rubber or plastic. 2. A thin, usually rectangular or square element of a structure that is capable of resisting lateral forces in its plane, such as a floor or roof. |
| Diaphragm Action | A bracing action that derives from the stiffness of a thin plane of material when it is loaded in a direction parallel to the plane; diaphragms in buildings are typically floor, or roof surfaces of plywood, reinforced masonry, steel decking, or reinforced |
| Diaphragm Pump | A water pump used to continuously remove water from excavations containing mud and small stones. |
| Diatomaceous Earth (DE) | Sedimentary rock deposits consisting of or abounding in diatoms or their siliceous remains; diatomite; used in water filters. |
| Diatomaceous Earth Filter | Pool filter using DE as filtering medium; one designed to filter water through a thin layer of filter aid such as diatomaceous earth or volcanic ash; diatomite filters may be of the Pressure or Vacuum type. |
| Dichlorodifluoromethane | Popular refrigerant known as Freon 12. |
| Dichlorodifluromethane | Refrigerant commonly known as R-12. |
| Dichromatic | Having two colors. |
| Die | 1. To cease living. 2. To stop. 3. An engraved metal device for stamping coins or medals. 4. A perforated steel block against which a material pressed to form a shape by extrusion. 5. An internally threaded tool used to cut threads on a pipe or rod. |
| Die Casting | Process of molding low-melting temperature metals in accurately shaped metal molds. |
| Diecast Set Screw | A set screw cast by forcing molten metal into a mold. |
| Dielectric Fluid | Fluid with high electrical resistance. |
| Diesel Generator | An electrical generator operated by diesel fuel. |
| Different Systems | Those which derive their supply from different sources, or from individual transformers or banks of transformers which do not have their secondary windings interconnected, or from individual service switches. |
| Differential | The temperature or pressure difference between cut-in and cut-out temperature or pressure of a control. |
| Differential Settlement | The uneven sinking of different parts or sections of a building's foundations. |
| Diffuse Radiation | Sunlight that is scattered from air molecules, dust and water vapor and comes from the sky vault. |
| Diffuse Transmission | Transmitted light that is scattered evenly in all directions as it passes through a material. |
| Diffuse-Porous Wood | Certain hardwoods in which the pores tend to be uniform in size and distribution throughout each annual ring or to decrease in size slightly and gradually toward the outer border of the ring. |
| Diffuser | 1. A device for distributing air in a forced air heating/cooling system; often flush-mounted on a ceiling, it has slats to direct the conditioned air evenly into the room or space; components of the ventilation system that distribute and diffuse air to pr |
| Diffuser, Suction | See Suction Diffuser. |
| Diffusion | The natural mingling of two or more substances to form a mixture or solution. |
| Digital | A digital instrument shows a measurement directly as a number, such as the LED display on a digital watch; compare with Analog. |
| Dike (groin, palisade, spur, jetty, deflector) | A structure designed (1) to reduce the water velocity as streamflow passes through the dike so that sediment deposition occurs instead of erosion (permeable dike) or (2) to deflect erosive currents away from the streambank (impermeable dike). |
| Dilapidation | A building in a state of neglect, disrepair, decay, ruin, or deterioration through neglect or misuse. |
| Diluent | In lacquer, the volatile portion of vehicle not capable by itself of dissolving nitrocellulose. |
| Diluents | See Thinners. |
| Dimension | 1. A measurable extent of any kind, such as width, length, height, or volume. 2. Dimension Lumber, See Dimension Stock. |
| Dimension Lumber | Lumber with a nominal thickness of from 2 inches up to but not including 5 inches and a nominal width of 2 inches or more; includes joists, planks, rafters, studs, and small timbers; see also Dimension Stock. |
| Dimension Ratio | The diameter of a pipe divided by the wall thickness; each pipe can have two dimension ratios depending on whether the outside or inside diameter is used; in practice, the outside diameter is used if the standards requirement and manufacturing control are |
| Dimension Stock | Hardwood stock processed to a point where the maximum waste remains at the dimension mill and the maximum utility is delivered to the user; stock of specified thickness, width, and length; according to specifications, it may be solid or glued up, rough or |
| Dimensional Stability | 1. The ability of a fabric to retain its dimensions in service and wet cleaning. 2. The ability of any material to maintain its essential dimensions in the conditions in which it is used. |
| Dimensional Stabilization | Measures taken to prevent or reduce warping, swelling. or shrinking. |
| Dimensions of Concrete Masonry Units | In practice, the first dimension of a CMU represents the thickness, the second, height; and the third, length. |
| Dimer | Formed by chemical combination of two similar molecules. |
| Diminish | To make or appear less or smaller. |
| Diminishing Returns | An increase in expenditure, investment, or taxation, beyond a certain point, ceases to produce a proportionate yield. |
| Diminution in Value | The amount by which the market value of property is reduced by any cause. |
| Dimmer Switch | A switch which controls the brightness of a light. |
| Dimple | The depression in the surface of gypsum board caused by a hammer as the nail head is set slightly below the surface or plane of the gypsum board to permit concealment with joint compound. |
| Diode | A semiconductor allowing the flow of current in one direction only and having two terminals. |
| Diorite | A granular, crystalline igneous rock commonly of acid plagioclase and hornblende, pyroxene, or biotite. |
| Dip Coating | Process of finishing an article by immersing it in finishing material. |
| Dip of a Trap | The lowest portion of the inside top surface of the channel through a plumbing trap; compare with Weir of a Trap. |
| Dipentene | Solvent made by destructive distillation of pine stumps; is stronger than turpentine. |
| Direct Burial Cable | Electrical cable that is suitable for burial directly in the earth without being in a conduit. |
| Direct Burial Conduit | Electric conduit suitable for burial in exterior applications with an outer surface that resists moisture, fungus, and corrosion. |
| Direct Costs | Costs which may readily be attached or directly related to the unit of production. |
| Direct Current (DC) | An electric current, of constant voltage, flowing in one direction only. |
| Direct Drive Fan | A fan that is positively connected in line to a motor to operate at the same speed. |
| Direct Examination | Questions directed to a friendly witness. |
| Direct Expansion (DX) | Interior air cooled by directly passing over an evaporator in which refrigerant is expanding from a fixed reference point. |
| Direct Expansion Evaporator | Evaporator using either an automatic expansion valve (AEV) or a thermostatic expansion valve (TEV) refrigerant control. |
| Direct Job Overhead | A firm's overhead expense that is directly attributable to completing a work in process and that would not be incurred if no projects were under way. |
| Direct Labor | The actual cost of labor payroll for all jobs worked on during the period covered by the income statement. |
| Direct Methods | Techniques of solar heating in which sunlight enters a house through the windows and is absorbed inside. |
| Direct Nailing | See Face-Nailing. |
| Direct nailing | To nail perpendicular to the initial surface or to the junction of the pieces joined. Also termed face nailing. |
| Direct Process | See American Process Zinc Oxide. |
| Direct Radiation | Solar radiation that comes straight from the sun, casting shadows on a clear day. |
| Direct Transmission | Light passing through a clear, transparent material. |
| Direct-Labor Burden | Includes all payroll taxes, insurance, and employees' benefits which are associated with the labor payroll. |
| Direction of Irrigation | Direction of flow of irrigation water; usually at right angles to the supply ditch or pipe. |
| Directional Arrow | A symbol used to denote direction. |
| Directional Sign | A publicly displayed notice which indicates by use of words or symbols a recommended direction or route of travel. |
| Directory Board | A panel that is used to display information. |
| Disability | 1. A physical or mental impairment that substantially limits one or more of the major life activities of an individual. 2. A record of such an impairment. 3. Being regarded as having such an impairment. |
| Disappearing Stair | A folding, hinged stairway that is pulled down from the ceiling and commonly hidden in a trap door. |
| Discharge | The volume of water passing through a channel during a given time, usually measured in cubic feet per second. |
| Discharge Valve | A special purpose valve. |
| Discharging Arch | An arch built over a lintel or header to help relieve the pressure from the wall above the arch; also known as a Relieving Arch or Safety Arch. |
| Discoloration | Change of color from that which is normal or desired. |
| Disconnect | A large (generally 20 Amp) electrical ON-OFF switch. |
| Disconnecting Means | A device, or group of devices, or other means whereby the conductors of a circuit can be disconnected from their source of supply. |
| Discount | 1. A deduction in price or the amount of a bill. 2. To sell a note for less than its principal sum; this has the effect of increasing the yield to the buyer. |
| Discount rate | A mortgage interest rate that is lower than the current rate for a certain period of time, e.g. 2.00% below variable rate for 2 years. |
| Discovery | A process in which parties to a lawsuit are required to divulge information. |
| Dishwasher | An electric appliance for washing dishes. |
| Disinfect Pipe | The act or process of transmitting an antimicrobial agent through a piping system. |
| Disinfectant | Chemical (also called bacteriacide) used to destroy germs and bacteria. |
| Disintegration | Decomposition into constituent elements or fragments. |
| Disk Sander | An electric sanding tool where the sand paper abrasive is mounted on a rotating disk. |
| Dismissal | The act of dropping a lawsuit. |
| Dispensary | A building or place where medicines and medical or dental aid are dispensed. |
| Dispenser, Tissue | See Tissue Dispenser. |
| Dispersed | Finely divided or colloidal in nature. |
| Dispersing Agent | An admixture capable of increasing the fluidity of pastes, mortars, or concretes by reduction of interparticle attraction; material used to aid in holding finely divided matter in dispersed state |
| Dispersion | 1.Suspension of one substance in another. 2. A suspension of very fine particles in a liquid medium, as in paints. |
| Displacement | Movement away from a fixed reference point. |
| Displacement, Piston | See Piston Displacement. |
| Disposal | 1. The process of disposing of something. 2. Garbage Disposal Unit. |
| Disposal Field | See Leaching Field. |
| Disposal Suit | A complete body suit worn by persons entering a hazardous materials area or handling hazardous materials. |
| Distemper | 1. A water paint in which the pigment is mixed with white or yolk of egg, casein or size and which is used for mural decoration. 2. Broadly any of numerous water-based paints for general, especially for household use. |
| Distensibility | Ability to be stretched. |
| Distillate | A condensed product produced by cooling vapors of a material heated sufficiently to drive off part of the material in the form of vapor. |
| Distillation | The process of vaporizing a liquid with heat and condensing the vapor to a liquid for the purpose of purification, fractionation, and forming new substances. |
| Distillery | A building or place where alcoholic liquor is distilled. |
| Distilling Apparatus | Fluid-reclaiming device used to reclaim used refrigerants; reclaiming is usually done by vaporizing and then recondensing the refrigerant. |
| Distortion | 1. The quality or state of being twisted out of a natural, normal, or original shape or condition. 2. A lack of proportion in an optical image resulting from defects in the optical system. 3. Faulty reproduction of radio sound or a television picture, cau |
| Distressed streambank | A bank that has (or is) suffering erosion or failure. |
| Distributed Load | A load on a structural member that is evenly applied along its entire length. |
| Distributing Pipes | The piping in a building that distribute the water received from the Service Pipe. |
| Distribution | 1. The movement of fresh concrete to its placement point. 2. The circulation of collected heat to living areas from collectors or storage. 3. The movement of any fluid or current to its end point. |
| Distribution Box | The main feed line terminus of an electrical service to which branch circuits are connected. |
| Distribution Panel | The main electrical control center, which contains switches or circuit breakers, is connected to the service wires, and delivers current to the various branch circuits. |
| Distribution Rib | A transverse thickening of a one-way concrete joist structure used to allow the joists to share concentrated loads. |
| Distyle | A building or structure having two columns in front. |
| Ditch | A long narrow excavation dug in the earth for foundation walls, sewer systems, irrigation systems, electrical cable lines, and utilities; a trench. |
| Divider, Hospital | See Hospital Divider. |
| Divider, Terrazzo | See Terrazzo Divider. |
| Dividers | A drafting tool, like a compass, but with two adjustable sharp points; used for marking out and scribing edges. |
| Diving Board | A narrow platform, often equipped with a spring and raised off the pool deck by a ladder, attached to the edge of a pool and extending over the water, used to give divers altitude and lift. |
| Diving Platform | Rigid stand for diving. |
| DIY | Do it yourself. |
| DLH Series | A standard Steel Joist Institute designation for longspan steel joists. |
| DOC | U.S. Department of Commerce, c/o National Institute of Standards & Technology, Gaithersburg, Maryland 20899, (301) 975-2000. |
| Dock Board | Heavy timber used in the construction of the raised platform used for the loading and unloading of trucks. |
| Dock Bumper | Thick rubber units placed under loading dock openings to absorb the shock and prevent damage when trucks back in for loading or unloading. |
| Dock Leveler | A mechanical device at a loading dock that adjusts to accommodate the different heights of truck beds. |
| DOE | U.S. Department of Energy. |
| Dog | Fits on a steel bar to form a tool for cramping or clamping. |
| Dog Leg | Any device that is crooked or bent like a dog's hind leg. |
| Dog’s Tooth | Brick so laid that their corners project from the face of the wall. |
| Dogging Device | A mechanism used on exit devices that fastens the cross bar in the fully depressed position, and also retains the latch bolt or bolts in a retracted position, thus permitting free operation of the door from either side. |
| DOI | U.S. Department of the Interior. |
| DOJ | U.S. Department of Justice. |
| Dolerite | Any of various coarse basalts or diabase. |
| Dolly Varden Siding | Beveled wood siding that is rabbeted on the bottom edge. |
| Dolomite | A mineral of the double carbonate of lime and magnesia having the general formula CaCO3MgCA3. |
| Dolomitic | A type of lime or limestone containing calcium carbonate in combination with up to 50% magnesium carbonate. |
| Dome | An arch rotated about a vertical axis passing through its crown, or highest point. |
| Dome Light | An overhead light. |
| Dome-Hat | Sealed metal container for the motor compressor of a refrigerating unit. |
| Domestic Marble | Marble which comes from the country or area where the structure in which it used is built. |
| Domestic Well | A water well dug for household use. |
| domette | An interlining with a padded weave. |
| Domette interlining | Imported from England, domette is a cotton interlining that is lighter than bump, table felt, reinforced felt, and flannel. Needle- punched fleece is the closest American equivalent to domette. These lightweight interlinings can be used for light curtains |
| Domicile | 1. A place of residence; a home. 2. A person's fixed, permanent, and principal home for legal purposes. |
| Dominant Color | Color that predominates or is outstanding. |
| Doodlebug | A device, as a divining rod, used in attempting to locate underground piping and conduits. |
| Doohickey | A small mechanical object whose name is not known or has been forgotten. |
| Door | A hinged, sliding, or revolving barrier for closing and opening an entrance to a building, room, or cupboard. |
| Door & Hardware Institute (DHI) | 14170 Newbrook Drive, Chantilly, Virginia 22021-2223, (703) 222-2010. |
| Door and Hardware Institute | 14170 Newbrook Drive, Chantilly, Virginia 22021-2223. |
| Door Buck | A door frame. |
| Door Bumper | Rubber tip device mounted on walls or baseboards that prevent door knobs from marring walls. |
| Door Closer | A mechanical device attached to a door to make it close automatically. |
| Door Coordinator | A device used on a pair of doors to ensure that the inactive leaf is permitted to close before the active leaf; necessary when an overlapping astragal is present and exit devices and automatic or self-latching bolts are used with closers on both door leav |
| Door Frame | The members that completely surround a door, made of wood or metal, to which the hinges are attached. |
| Door Frame Grout | Grout to fill in the voids where a masonry structure meets a metal door frame. |
| Door Guard | Guard fabricated of steel components to provide protection over interior face of door or prevent damage to glass and to prevent intrusion. |
| Door Head | The assembly of parts at the top of a door frame including the frame, stop, casing, shims, and flashing. |
| Door Header | Horizontal beam placed on vertical jack studs which form the uppermost portion of the framing of a door opening. |
| Door Holder | A device used to hold a door in an open position. |
| Door Jamb | The vertical members of a door frame. |
| Door Knob | A projecting knob for operating a lock. |
| Door Louver | Slanted fins, either fixed or movable, provided on a door for ventilation. |
| Door Motor | A mechanical device operated by electric current which opens or closes a door. |
| Door Opener | An electronic device which when activated opens a door by mechanically unlatching the throw bolt of a doorknob or which opens a door on a pivot point on the hinge side of the door. |
| Door operator | An automatic garage door opener. |
| Door Paint | A specific paint, usually a latex or alkyd enamel, used for its ability to be washed, to withstand cracking and scratch resistance. |
| Door Pull | A handle by which a door is pulled. |
| Door Rail Hanger | Structural steel shape used to support large rolling door. |
| Door Removal | The act or process of removing a door from its hinges. |
| Door Seal | Rubberized material attached to door head, jamb, and bottom of a door to aid in preventing air drafting. |
| Door Stop | A molding nailed to the faces of the door frame jambs to prevent the door from swinging through. |
| Door Switch | An electric switch installed in a door jamb which turns on a light in a closet when the door is opened and turns off a light when the door is closed. |
| Door Threshold | See Threshold, Door. |
| Door Trim | 1. Wood or metal finishing work, often ornamental, used for covering the joints between door jambs and plaster walls. 2. The locks, knobs and hinges on a door. |
| Door, Access | See Access Door. |
| Door, Aluminum | A glazed door constructed with aluminum stiles and rails. |
| Door, Chain Hoist | A door that is operated by a chain placed in a pulley or sheave. |
| Door, Commercial | See Commercial Door. |
| Door, Flush | See Flush Door. |
| Door, Folding | See Folding Door. |
| Door, Hollow Core | See Hollow Core Door. |
| Door, Overhead | See Overhead Door. |
| Door, Revolving | See Revolving Door. |
| Door, Roll-Up | See Roll-Up Door. |
| Door, Shower | See Shower Door |
| Door, Sliding Glass | See Sliding Glass Door. |
| Door, Solid Core | See Solid Core Door. |
| Door, Special | See Special Door. |
| Door, Vault | See Vault Door. |
| Door, Vertical Lift | See Vertical Lift Door. |
| Doorjamb, interior | The surrounding case into which and out of which a door closes and opens. It consists of two upright pieces, called side jambs, and a horizontal head jamb. These 3 jambs have the "door stop" installed on them. |
| Dope | A term used by plasterers for mortar additives of any type, such as those used to retard or accelerate set. |
| Dope Coat | In tile setting, neat cement applied to the setting bed. |
| Dormer | An opening in a sloping roof, the framing of which projects out to form a vertical wall suitable for windows or other openings. |
| dormer window | A window, usually small with vertical sides and front, set into the slope of a roof and projecting from it. |
| Dormitory | A room occupied by more than two guests. |
| Dormitory Wardrobe | A closet in student housing where clothes are kept; commonly a free-standing cabinet made to match the cabinets of the dormitory room. |
| Dot | A small lump of plaster placed on a surface between grounds to assist the plasterer in obtaining the proper plaster thickness and aid in aligning the surface; see Screed, 1. |
| DOT | U.S. Department of Transportation, 400 Seventh Street, SW, Washington, DC 20590-0001, (202) 366-4488. |
| Dote | Wood rot or decay. |
| dotted Swiss | A sheer fabric with opaque dots which are sometimes flocked to create a raised texture. |
| Double Back | A webbed backing cemented to the backing of tufted, knitted and some woven carpets as additional reinforcement, to provide greater dimensional stability; also called Scrim Back. |
| Double Bullnose | A type of trim with the same convex radius on two opposite sides. |
| Double Duty Case | Commercial refrigerator in which a part of space is for refrigerated storage and part is equipped with glass windows for display purposes. |
| Double glass | Window or door in which two panes of glass are used with a sealed air space between. Also known as Insulating Glass. |
| Double Glazing | Two parallel sheets of glass with an airspace between;also called Dual Glazing or Double Glass. |
| Double Headed Nail | A nail with two closely-spaced heads to permit easy removal; widely used in concrete formwork as a temporary fastener; also called a Duplex Nail. |
| Double Hung Window | The most common style of operable window, it has two sashes that slide vertically in parallel tracks; a window with two overlapping sashes that slide vertically in tracks. |
| Double Layer | Two layers of gypsum board; various thicknesses may be combined to improve the fire, sound, or structural characteristics. |
| Double Nailing | A method of applying gypsum board by using two nails spaced approximately 2 inches apart every 12 inches in the field along the framing member to insure firm contact with the framing. |
| Double Offset | In piping, two offsets installed in succession in the same line. |
| Double Oven | An oven with two baking compartments. |
| Double Plate | The two wood plates on the top of a wood framed wall. |
| Double Regulation | Regulation of both pot and gun air pressure. |
| Double Reinforcement | A concrete beam with steel on both sides of the neutral axis to resist tension and compression. |
| Double Seal | A seal coat (refer seal) consisting of two successive applications. |
| Double Spread | See Spread. |
| Double Stud | Two adjoining studs in a wood framed wall. |
| Double Tee | A precast concrete slab element that resembles the letters TT in cross section. |
| Double Thickness Flare | Copper, aluminum or steel tubing end which has been formed into two-wall thickness, 37 to 45 degrees bell mouth or flare. |
| Double Walled Tank | A tank constructed with two walls for leak protection and to increase strength and stability. |
| Double Wye | A fitting or branch pipe in plumbing, constructed of either cast or wrought iron, which has two side outlets at any angle except a right angle; usually a 45 degree angle. |
| Double-Back | See Double-Up. |
| Double-Bevel Groove Weld | See Groove Weld. |
| double-hung window | A window consisting of an upper sash and a lower sash that slide vertically. The sashes may be divided into panes. |
| Double-J Groove Weld | See Groove Weld. |
| Double-U Groove Weld | See Groove Weld. |
| Double-Up | A method of plaster placement characterized by application in successive operations with no setting or drying time allowed between coats; also called Double-Back, Doubled-Up, Laid Off, Laid On, or Two Coat Work. |
| Double-Vee Groove Weld | See Groove Weld. |
| Doubled-Up | See Double-Up |
| Douglas Fir | A tall, evergreen tree that furnishes long straight framing lumber; also known as Red Fir, Douglas Spruce, and Yellow Fir. |
| Douglas Fir Plywood Association (DFPA) | c/o American Plywood Association), PO Box 11700 Tacoma, Washington 98411, (202) 272-2283. |
| Douglas Spruce | Douglas Fir. |
| Dovecote | A shelter for nesting doves. |
| Dovetail Anchor Slot | A matching interlocking strip or slot which is used with a dovetail fastener. |
| Dovetail Joint | A joint in which one piece has dovetail shaped pins or tenons which fit into corresponding openings on the other piece. |
| Dovetail Saw | Saw used for cutting very accurate joints; similar to a tenon saw but with a thinner blade and finer teeth. |
| Dowel | 1. A steel bar, which extends into two adjoining portions of a concrete or masonry construction, as at a joint in a pavement slab, so as to connect the portions and transfer shear loads. 2. As used in the construction of column and wall sections, a deform |
| Dowel Pin | Dowel. |
| Dowel Sleeve | Cap of light metal or cardboard on one end of a steel dowel bar to allow free movement of an expansion joint. |
| Down Payment | The money paid by the buyer, being the difference between the full price and the borrowings. |
| Down Time | The time during which equipment is out of service for essential maintenance or emergency repairs. |
| Downdrift | The longshore direction of predominant movement of littoral materials. |
| Downspout | Vertical pipe usually made from sheet metal or plastic which carries water from the roof gutters to the ground or a storm drain; also called a Leader. |
| Downspout Boot | Device at bottom of downspout to receive water from downspout and provide transition to drainage piping. |
| Downspout Bracket | A metal bracket for securing a downspout to a wall. |
| Dozer | A term used in the trade for a bulldozer. |
| Dozer Excavation | The digging out of large areas of earth with a bulldozer. |
| Draft Gauge | Instrument used to measure air movement by measuring air pressure differences. |
| Draft Indicator | Instrument used to indicate or measure chimney draft or combustion gas movement; draft is measured in units of .10 in. of water column. |
| Draft Regulator | Device which maintains a desired draft in a combustion-heated appliance by automatically controlling the chimney draft to the desired value. |
| Drafter | Draftsman. |
| Drafting Board | A flat surface used by drafters on which to produce drawings. |
| Drafting Machine | A mechanical device with adjustable straight edges that may be clamped onto a drawing board for use by a drafter. |
| Draftsman | 1. One who prepares architectural, construction, or engineering drawings; draftsman. 2. A person who drafts documents. |
| Drag | In welding, the distance between the point of exit of the cutting oxygen stream and the projection on the exit surface of the point of entrance. |
| Drag Strut | A structural member used to transfer lateral forces from one vertical element to another. |
| Dragging | See Floating. |
| Dragline | A bucket attachment for a crane commonly used in a marsh or marine area, that digs soft materials that must be excavated at some distance from the crane, and draws the bucket towards itself using a cable. |
| Dragon's Blood | A red gum exuded from the fruit of a species of palm; used for coloring varnish; the color is not permanent. |
| Drain | 1. A trench, ditch, or pipe designed to carry away waste water. 2. A device that allows for the flow of water from a roof area. |
| Drain Board | A countertop adjoining a sink. |
| Drain Field | A system of trenches filled with sand, gravel or crushed stone, and a series of pipes to distribute septic tank effluent into the surrounding soil. |
| Drain Pipe | Any pipe that carries waste or water-borne wastes in a building drainage system. |
| Drain Tile | Short-length sections of burned clay, plastic, or concrete pipe, laid with open joints and surrounded with aggregate and covered with asphaltic paper or straw to drain the water from an area. |
| Drain, Intercepting (Curtain Drain) | A drain that intercepts and diverts ground water before it reaches the area to be protected. |
| Drain, Waste and Vent (DWV) System | The assemblage of pipes which facilitates the removal of liquid and solid wastes as well as the dissipation of sewer gases. |
| Drainage | 1. The process or means of draining a building or land area of atmospheric moisture or sewage. 2. A system of drains, artificial or natural. |
| Drainage Head | The farthest or highest spots in a drainage area. |
| Drainage Pipe | Any pipe in a plumbing system which removes waste water, rainwater, or sewage. |
| Drainage System | All drain and waste pipes that carry water and waste away from the fixtures. |
| Drainage, Underslab | The process of continuous interception and removing of ground water from under a concrete slab with the installation of crushed stone and perforated pipe. |
| Drape | A window covering; curtain. |
| drapery | A heavy-full-length curtain with a pleated heading; the term is often shortened to ìdrape.î It is also used to mean draped fabric such as a swag. |
| Drapery Rod | A wall-mounted wood or metal shaft for supporting drapery. |
| Drapery Track | A U-shaped device mounted to a door or window header, ceiling or floor, used as a guide for draperies. |
| Draughtsman | Draftsman; drafter. |
| Draw | The amount of progress billings on a contract that is currently available to a contractor under a contract with a fixed payment schedule. |
| Draw Board | A board fitted in a kitchen cabinet that may be pulled out to create a supplementary work surface, like a breadboard. |
| draw rod | Rod inserted into the heading used to open and close curtains. |
| Drawboard Joint | A mortise-and-tenon joint with holes so bored that when a pin is driven through, the joint becomes tighter. |
| Drawbridge | A bridge over water, hinged at one end so that it may be raised or lowered to allow or prevent passage of ships. |
| Drawer | A sliding boxlike storage compartment, usually part of a cabinet. |
| Drawer Knob | A cabinet knob. |
| Drawer Pull | A handle with which to withdraw a drawer. |
| Drawer Roller | A device used to ease the sliding of a drawer open or shut, usually with a metal or fiber wheel rotating in a metal frame. |
| Drawer Slides | A mechanism employing guides and rollers that guide and support the drawer, permitting easy operation. |
| Drawing Room | A formal reception room; a withdrawing room. |
| Drawings | Graphic representations of buildings and their parts; plans or blueprints. |
| Drawings, Shop | Drawings of specific items of the project provided by subcontractors or fabricators. |
| Drawn Glass | Glass sheet pulled directly from a container of molten glass. |
| Drayage | The charge for transportation or delivery of goods. |
| Dredge | Deepen a waterway by use of a dredging machine, usually mounted on a barge. |
| Dredge material | Soil that is excavated from a stream channel, lake or other body of water. |
| dress curtains | Curtains that are never intended to be closed; used for decorative purposes only. |
| Dressed and matched (tongued and grooved) | Boards or planks machined in such a matter that there is a groove on one edge and a corresponding tongue on the other. |
| Dressed Size | The dimensions of lumber after being surfaced with a planing machine; the dressed size is usually 1/2 to 3/4 inch less than the nominal or rough size; a 2- by 4-inch stud, for example, actually measures about 1-1/2 by 3-1/2 inches. |
| Dressing Room | 1. In a home, a room for storage of clothes and for dressing. 2. In a theater, a room for storing and changing costumes and for applying and removing make-up. |
| Drier | 1. Substance or device used to remove moisture from a refrigeration system. 2. A solution added to drying oils in paint to quicken the drying. 3. Composition of certain metals that accelerate drying action of oil when added to paint or varnish; some drier |
| Drier paint | Usually oil-soluble soaps of such metals as lead manganese, or cobalt, which, in small proportions, hasten the oxidation and hardening (drying) of the drying oils in paints. |
| Drift | 1. Lateral deflection of a building caused by wind or earthquake loads; the horizontal displacement or movement of structure when subjected to lateral forces. 2. Spray loss, in using a spray gun; also called Overspray. |
| Drift Pin | A tapered steel shaft used to align bolt holes in steel connections during erection. |
| Drill | Common name for small boring bit and for the electric drill. |
| Drilled Well | The act or process of using a rotary drill to dig for water. |
| Drilling Rock | The act or process of boring holes into rock. |
| Drip | (a) A member of a cornice or other horizontal exterior finish course that has a projection beyond the other parts for throwing off water.(b) A groove in the underside of a sill or drip cap to cause water to drop off on the outer edge instead of drawing ba |
| Drip | 1.A painting defect where the paint has started to run. 2. A projecting piece of material so shaped as to throw off water and prevent its running down the face of the wall or other surface of which it is a part. |
| Drip cap | A molding or metal flashing placed on the exterior topside of a door or window frame to cause water to drip beyond the outside of the frame. |
| Drip Edge | A discontinuity or strip installed at roof eaves or over a window or wall component to force adhering drops of water to fall free of the face of the building rather than run toward the interior; the projection of a window head member or water table to all |
| Drip Loop | A low spot in an aerial wire to allow atmospheric moisture and rainwater to drip off before the wire enters the building. |
| Drip Pan | Pan-shaped panel or trough used to collect condensation from evaporator. |
| Drippage | Leakage of roofing bitumen through cracks in the roof deck or over the edges of the roof. |
| Drive Screw | A screw which is driven in with a hammer but removed by a screwdriver. |
| Drive-Up Window | An opening in a wall through which transactions can be made with persons in motor vehicles. |
| Driveway | A passageway for automobiles on private property. |
| Driveway Apron | A sloping transition from the public street to a private driveway. |
| Driving Cap | A steel cap placed on the top of a pile for protection from damage during driving. |
| Drop Black | Bone Black. |
| Drop Cloth | A canvas, plastic, or paper protective sheet used by painters to cover floors and furniture. |
| Drop Match | See Set Match. |
| Drop Panel | A thickening of a two-way concrete floor structure at the head of a column. |
| Dropback | Softening Point Drift. |
| Drum Trap | A cylindrical plumbing trap, closed at the bottom, with a cover for cleaning; the pipe from the fixture enters the trap near the bottom; the space between where the pipe enters and the bottom is a settling area; the outlet to the waste pipe is higher up i |
| Dry Air | Air that contains no water vapor. |
| Dry Bulb (DB) Temperature | The temperature of air as registered by an ordinary thermometer; compare with Wet Bulb Temperature. |
| Dry Capacitor Condenser | Electrical device made of dry metal and dry insulation; used to store electrons. |
| Dry Cell Battery | Electrical device used to provide DC electricity, having no liquid in the cells. |
| Dry Cleaner | An apparatus for the washing of fabrics which uses substantially non-aqueous organic solvents. |
| Dry Edging | Rough edges and corners of glazed ceramic ware due to insufficient glaze coating. |
| Dry Film Thickness | Depth of applied coating when dry, expressed in mils. |
| Dry Ice | Refrigerating substance made of solid carbon dioxide which changes directly from a solid to a gas (sublimates). Its subliming temperature is -109 F. (-78 C.). |
| Dry in | To install the black roofing felt (tar paper) on the roof. |
| Dry Kiln | A chamber having controlled air-flow, temperature, and relative humidity for drying lumber, veneer, and other wood products. |
| Dry Lap | The absence of bitumen at the overlap of two roofing felts. |
| Dry Location | A location not normally subjected to dampness or wetness; a location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction. |
| Dry Mix | A concrete or mortar mix in which there is little or no water. |
| Dry Oil | See Dehydrated Oil. |
| Dry Pack | A mixture of cement and fine aggregate with enough moisture for hydration but dry enough to be rammed into place. |
| Dry Press Brick | Brick formed in molds under high pressures from relatively dry clay, 5 to 7 percent moisture content. |
| Dry Rodded Weight | The weight of dry aggregate rodded into a cylindrical container of diameter approximately equal to the height, each of 3 layers rodded 25 times, and the excess aggregate struck off level with the top of the container. |
| Dry Rot | A term loosely applied to any dry, crumbly rot but especially to that which, when in an advanced stage, permits the wood to be crushed easily to a dry powder; the term is actually a misnomer for any decay, since all fungi require considerable moisture for |
| Dry Set Mortar | A water-retentive hydraulic cement mortar usable with or without sand; when this mortar is used, neither the tile nor walls have to be soaked during the installation process. |
| Dry Set Tile | Tile set into an adhesive that seems dry but that adheres on contact. |
| Dry Sheet | A ply of roofing felt mechanically attached to the deck to prevent asphalt or pitch from leaking into the building below; dry sheets are not part of built-up roofing assemblies. |
| Dry Spots | Small areas on the face of tile which have been insufficiently glazed. |
| Dry Spray | Overspray or bounce back; sand finish due to spray particle being partially dried before reaching the surface. |
| Dry Sprinkler System | A fire extinguishing sprinkler system whose pipes remain empty of water until the system is activated. |
| Dry Standpipe | A fire fighting pipeline in a building that is dry until filled by external connection to a fire hydrant. |
| Dry Stone Wall | A wall of stone that has been constructed without the use of mortar or concrete in its joints. |
| Dry System | Refrigeration system which has the evaporator liquid refrigerant mainly in the atomized or droplet condition. |
| Dry Tape | The application of tape over gypsum board joints with adhesives other than conventional joint compound. |
| Dry To Handle | 1. A film of paint is dry to handle when it is hardened sufficiently so that it may be handled without being damaged. 2. Time interval between application and ability to pick up without damage. |
| Dry To Recoat | In painting, time interval between application and ability to receive next coat satisfactorily. |
| Dry To Touch | 1. A film of paint is dry to touch when it is hardened sufficiently so that it may be touched lightly without any of it adhering to the fingers. 2. Time interval between application and tack-free time. |
| Dry Type Extinguisher | A fire extinguishing system that discharges a dry powder by means of compressed gas. |
| Dry Type Spray Booth | A spray booth where an inhibitor has been added to paint to prevent the surface from drying too rapidly, causing wrinkling or cracking. |
| Dry Type Transformer | A transformer whose coils and core are not immersed in an oil bath. |
| Dry Vent | A plumbing vent that does not carry any liquids; it acts as a vent only and carries only air. |
| Dry Well | A deep hole, covered and usually lined or filled with rocks, that holds drainage water until it soaks into the ground. |
| Dry-Out | A condition occasionally occurring in gypsum plaster work which by excessive evaporation or suction has lost some or all of the water necessary for crystallization; appears as a light colored, friable area. |
| Dryer | An apparatus that will dry the aggregates and heat them to the specified temperatures. |
| Dryer Receptacle | An electrical outlet wired to match the specific electric current needs and configuration of a clothes dryer. |
| Dryer, Coin | See Coin Dryer. |
| Dryer, Darkroom | See Darkroom Dryer. |
| Drying | Act of changing from liquid to solid state by evaporation of uncombined water and volatile thinners and by oxidation of oils. |
| Drying Oil | An oil which, when a thin film of it is exposed to the air, takes on oxygen and becomes hard, tough, and elastic; drying oils are used in the manufacture of paints and varnishes; linseed oil is a common drying oil. |
| Drying Shrinkage | A decrease in the volume of concrete upon drying. |
| Drying Time | Time interval between application and final cure. |
| Dryness | 1. The condition of being free of liquid, especially water. 2. The degree of free moisture contained within a gypsum board product. |
| Drywall | 1. Wall materials that do not involve the use of plaster, such as gypsum wallboard or wood paneling. 2. A gypsum board product, usually gypsum wallboard. |
| Drywall | Interior covering material, such as gypsum board or plywood, which is applied in large sheets or panels. |
| Drywall (or Gypsum Wallboard (GWB), Sheet rock or Plasterboard) | Wall board or gypsum- A manufactured panel made out of gypsum plaster and encased in a thin cardboard. Usually 1/2" thick and 4' x 8' or 4' x 12' in size. The panels are nailed or screwed onto the framing and the joints are taped and covered with a 'joint |
| Drywall Removal | The act or process of demolishing and carrying away old drywall systems in a building or structure. |
| Drywall Studs | Light gauge metal studs that fit into a top and bottom track to support sheets of gypsum wallboard for constructing interior non-bearing partitions. |
| Drywall Track | The horizontal light gauge metal top and bottom wall members in an interior gypsum wallboard non-bearing partition. |
| Drywood Termites | See Termite. |
| DS | Downspout. |
| DS Glass | Double strength window glass. |
| Dual Duct Air Handling System | A system similar to a multi-zone system, except that instead of mixing the hot and cold at the air handling unit, separate hot and cold ducts are run to the space to be conditioned, and a terminal mixing box is provided at the space to be conditioned; a c |
| Dual Glazing | Double Glazing. |
| Dual Vents | A plumbing vent that connects at the point where two fixture drains come together and acts as a back vent for both fixtures' traps. |
| Duct | A pipe, tube, or channel carrying air, gas, liquid, or wires. |
| Duct Bank | A group, series, or tier of round or rectangular metal pipes used to distribute warm or conditioned air throughout a building or structure. |
| Duct Guard | Special additive in the paint of a miniblind made by Levolor which repels dust. |
| Duct Heater | A heating element in a duct of an air-handling system. |
| Duct Insulation | The material installed on the ductwork in an HVAC system, for the reduction of fire hazard, or as thermal insulation. |
| Duct Shaft | A lined vertical shaft in a building, usually of a fire-rated construction, through which air ducts and piping are run. |
| Duct Tape | A tough adhesive tape used to assemble and to repair light gauge air ducts. |
| Duct, Bus | See Bus Duct. |
| Duct, Feeder | See Feeder Duct. |
| Duct, Underfloor | See Underfloor Duct. |
| Ductile | 1. In structures, the ability of a material to deform under tensile load. 2. Of metals, capable of being drawn out into wires, rods, or thin shapes. |
| Ductile Iron Pipe | Iron pipe that is manufactured so as to render it able to be flexed; ductile iron pipe has the non-corrosive qualities of cast iron but is not brittle and has the handling characteristics of steel. |
| Ductile Moment Resisting Space Frame | A three dimensional structural system without bearing walls and composed of interconnecting members that resist lateral forces with or without the aid of horizontal diaphragms. |
| Ductility | 1. The quality of being able to deform considerably under load before fracturing; contrasted to the quality of brittleness. 2. The ability of a substance to be drawn out or stretched thin; while ductility is considered an important characteristic of aspha |
| Ducts | The heating system. Usually round or rectangular metal pipes installed for distributing warm (or cold) air from the furnace to rooms in the home. Also a tunnel made of galvanized metal or rigid fiberglass, which carries air from the heater or ventilation |
| Ductwork, Metal | The rigid sheet material out of which the ducts of an HVAC system are manufactured, commonly, galvanized sheet steel, aluminum, or stainless steel. |
| Due Process | Notice, and an opportunity to be heard. |
| Due-on-sale | A clause in a mortgage contract requiring the borrower to pay the entire outstanding balance upon sale or transfer of the property. |
| Duette | Honeycomb shade made by Hunter Douglas. Huge assortment of colors, pleat sizes, and special options. |
| Duette Duolite | Two Duette shades stacked on top of one another. The bottom usually black out and the tip usually a sheer. |
| Dull | Term applied to colors that have a neutral or grayed quality. |
| Dull Rubbing | Act of rubbing a dried film of finishing material to a dull finish, usually with abrasive paper, pumice stone, steel wool, and oil or water. |
| Dulling | Loss of gloss or sheen. |
| Dumbwaiter | A small elevator used for conveying food, dishes, or materials from one floor to another in a building. |
| Dummy Joint | A joint placed strictly for design, in sidewalks and patios. |
| Dummy Trim | Hardware trim only, without a lock, usually used on the inactive door in a pair of doors. |
| Dump Fee | The amount charged for dumping jobsite debris in a landfill or dumpsite. |
| Dump Truck | A truck with a tiltable body used for transporting and dumping loose materials. |
| Dumpster | A large, heavy metal container used to hold and haul rubbish. |
| Dumpy Level | An Engineer's Level. |
| Dunes | Ridges or mounds of loose, wind-blown material, usually sand. |
| Dunnage | 1. Loose materials used around a cargo to prevent damage. 2. Scrap gypsum board used for protection of a shipping unit of gypsum wallboard. |
| Dunting | The cracking that occurs in fired ceramic bodies due to thermally induced stresses. |
| dupion | Real or artificial silk with a slubbed, or textured, surface. Real silk dupion is generally imported from India; it is a lightweight fabric which, like other silks, tends to fade and rot. Artificial dupion is made of acetate and viscose. |
| Duplex | 1. A two-family house. 2. A Duplex Apartment. |
| Duplex Apartment | An apartment having rooms on two floors. |
| Duplex Box | An electrical box for wiring switches or duplex receptacles. |
| Duplex Nail | A Double Headed Nail. |
| Duplex Paper | Wallpaper which consists of two separate papers pasted together; used to create a highly embossed effect. |
| Duplex Plate | A protective, finished, plate installed over duplex switches or receptacles. |
| Duplex Receptacle | A double electric outlet. |
| Dura board, dura rock | A panel made out of concrete and fiberglass usually used as a ceramic tile backing material. Commonly used on bathtub decks. Sometimes called Wonder board |
| Durability | 1. Ability to exist for a long time without significant deterioration. 2. The ability of concrete to resist weathering action, chemical attack, and abrasion. 3. The property of an asphalt paving mixture that describes its ability to resist disintegration |
| Duress | Compulsion. |
| Durham | A type of pipe system composed of iron or steel pipe and all of the joints are threaded screw joints; the fittings used in this system are recessed drainage fittings. |
| Dust Cap | A protective cap placed over a device to protect it from the intrusion of foreign materials. |
| Dust Free | A film of paint is dust free when dust no longer adheres to it. |
| Dust Mask | A fabric mask worn to filter out dust and other foreign matter. |
| Dust Shield | Special additive in the paint of a miniblind made by Hunter Douglas which repels dust. |
| Dust-Tight | So constructed that dust will not enter the enclosing case. |
| Dusting | 1. The application of dry portland cement to a wet floor or deck mortar surface; a pure coat is thus formed by suction of the dry cement. 2. The development of powdered material on the surface of hardened concrete caused by inadequate curing. |
| Dustproof | So constructed or protected that dust will not interfere with its successful operation. |
| Dutch Bond | In masonry, a bond having the courses made up alternately of headers and stretchers; same as English Bond. |
| Dutch Door | A door with two separately hinged leaves, one above the other, enabling one to be open while the other stays shut. |
| Dutch Door Bolt | Device for locking together the upper and lower leaves of a Dutch door. |
| Dutch Metal | Thin leaves of bright brass which are used for overlaying in the same manner in which gold leaf is applied. |
| Dutchman | 1. A small wood patch in woodwork. 2. A cut tile used as a filler in the run of a wall or floor area. 3. A narrow strip of carpet side- seamed to standard-width broadloom to compensate for unusual offsets and sloping walls but never used as a substitute f |
| Duty | An obligation that is imposed by law or by contract. |
| Duty, Continuous | See Continuous Duty. |
| Dwarf Wall | A short wall or partition that does not reach the ceiling. |
| Dwelling | A place in which people live. |
| Dwelling Unit | One or more habitable rooms which are intended or designed to be occupied by one family with facilities for living, sleeping, cooking, and eating. |
| DWV | Drainage, waste, and vent system. |
| DX | Direct Expansion. |
| DYE | A material used for dyeing or staining. |
| Dynamic | Having to do with bodies in motion; implying motion or change of state; for example, an earthquake force is a dynamic force; the opposite of Static. |
| Dynamic Force | A moving force; F=ma, or force equals mass times acceleration. |
| Dynamite | A type of explosive; a slang term used by tilesetters when referring to a mortar accelerator. |
| Dynamo | An electrical power generator. |
| Dynamometer | Device for measuring power output or power input of a mechanism. |
| Dyne | A unit of force that, acting on a mass of one gram, increases its velocity by one centimeter per second along the direction that it acts. |