Search Results for D D.H. Double hung damp-proofing An application of a water-resisting treatment or material to the surface of a concrete or masonry wall to prevent passage or absorption of water or moisture. Can also be accomplished by using an admixture in the concrete mix. dead air space Unventilated air space between structural elements. The space is used for thermal and sound insulation. dead level The state of being absolutely level, with no pitch or slope. deck The flooring of a building. decking Light-gauge, corrugated metal sheets used in constructing roof and floors. defect Any condition or characteristic that detracts from the appearance, strength, or durability of an abject. deflection The bending of a structural member as a result of its own weight or an applied load. delamination Separation of plies of materials, usually due to failure of an adhesive. dentils Square, tooth-like blocks used as ornaments under a cornice. desiccate To dry thoroughly or to make dry by removing the moisture content, as in the seasoning of timber by exposing it in an oven to a current of hot air. design load In structural analysis, the total load on a structural system under the worst possible loading conditions. design ultimate load (factored load) The working load multiplied by the load factor. design/build (design/construct) A method of construction in which the contractor provides both design and construction services to an owner. detail A large-scale architectural or engineering drawing indicating specific configurations and dimensions of construction elements. dewpoint The temperature at which air of a given moisture content becomes saturated with water vapor. diagonal brace A member installed at an angle to make a rectangular frame more rigid. diagonal bridging Crossing pairs of diagonal bracing that extend between the top of one floor joist and the bottom of the adjacent joist. The bracing is used to distribute the load and to decrease deflection. diagonal sheathing A covering of wooden boards placed diagonally over as exterior stud wall. Although slightly more expensive to install, this method provides a more rigid frame than horizontally installed boards, and may be more architecturally pleasing. differential settlement Uneven, downward movement of the foundation of a structure, usually caused by varying soil or loading conditions and resulting in cracks and distortions in the foundations. diffuser A circular, square, or rectangular air distribution outlet, generally located in the ceiling, and comprised of deflecting members to discharge supply air in various directions. distributed load A load distributed evenly over the entire length of a structural member or the surface of a floor or roof, expressed in weight per length or weight per area. distribution board (distribution panel, distribution switchboard) An electric switchboard or panel used to distribute electricity within a building. The switchboard is enclosed in a box and contains circuit breakers, fuses, and switches. DL Dead load, deadlight, diesel door casing The finished visible frame into which a door fits. door closer A device that controls the speed and force of closure of a door. dormer A projection through the slope of a roof for a vertical window. double angle A structural member formed by using two L-shaped angle irons back to back. double door Two single doors or leaves hung in the same doorframe. double floor A floor constructed with a sub-floor under a finished wood floor. double-hung window A window that has two vertical sliding sashes, one above the other, mounted on separate guides so that either or both can be opened at one time. This is the type of window most commonly used in wood-frame houses. dowel lubricant A lubricant applied to dowels placed in adjoining concrete slabs to allow longitudinal movement in expansion joints. dowel-bar reinforcement Short sections of reinforcing steel that extend from one concrete pour into the next. Used to increase strength in the joint. drain tile Short-length sections of tile laid with open joints, usually surrounded with aggregate and covered with asphaltic paper or straw. Used to drain the water from an area. drainage system All the components that convey the sewage and other wastewater to a point of disposal. dressed lumber (dressed stuff) Lumber that has been processed through a planing machine in order to attain a smooth surface and uniformity of size on at least one side or edge. drip A groove in the underside of a projection, such as a windowsill, that prevents water from running back into the building wall. drop ceiling (dropped ceiling) A nonstructural ceiling suspended below the structural system, usually in a modular grid pattern. A drop ceiling usually contains a lighting system. drop chute A device, much like as elephantís trunk, used to place concrete with a minimum amount of segregation. drop wire An electrical conductor dropped from a pole to a building to supply electric power to the building. dropped girder (dropped girt) A girder that runs below the floor joists and supports them. dry area A narrow roofed area between a basement wall and a retaining wall, constructed to keep the basement wall dry. dry-pipe sprinkler system (dry sprinkler) A sprinkler system whose pipes remain empty of water until the system is activated. This type of system is particularly useful where there is danger of freezing. drywall Interior finish construction materials that are manufactured and installed in preformed sheets, such as gypsum wallboard. Drywall is an alternative to plaster. duct In HVAC systems, the conduit used to distribute the air. Dur-O-Wal Trade name for horizontal reinforcement in masonry design. dusting The development of dust on the surface of a concrete floor. Dusting can result from troweling too soon, too much water in the mix, improper mix design, and other reasons. dwg, DWG Drawing dynamic load A load on a structural system that is not constant, such as a moving live load or wind load. Search Again