Search Results for M M Thousand, bending moment (on drawings) main In electricity, the circuit that feeds all sub-circuits. main beam A structural beam that transmits its load directly to columns, rather than to another beam. main rafter A structural roofing member that extends from the plate to the ridgepole at right angles. main tie In a roof truss, the bottom straight member that connects the two feet. makeup air unit A unit to supply conditioned air to a building to replace air that has been removed by an exhaust system or by combustion. manhole A vertical access shaft from the ground surface to a sewer or underground utilities, usually at a junction, to allow cleaning, inspection, connections, and repairs. mansard roof A roof with a double pitch on all four sides, the lower level having the steeper pitch. marquee A canopy extending out from an entrance for protection from the weather. masonite A trade name for a nonstructural building board about º" thick, usually with one surface hard and smooth. Masonite can be either tempered or untempered, the untempered form being harder and more water-resistant. masonry Construction composed of shaped or molded units, usually small enough to be handled by one man and composed of stone, ceramic brick or tile, concrete, glass, adobe, or the like. masonry bonded hollow wall A hollow masonry wall in which the inner and outer wythes (thicknesses) are tied together with masonry units rather than metal ties. masonry pointing Troweling mortar into a masonry joint after the masonry units have been laid. masonry reinforcing Refers to both the lateral steel rods or mesh laid between the courses of masonry units and the vertical rods that are grouted into the voids. master A term applied to the third and highest level of achievement for a tradesman or mechanic, who by supervision, experience, and examination has earned a masterís license attesting that he is a master of the trade and no longer requires supervision of his work, as is the case with the journeyman and apprentice levels. MASTERFOR-MAT The name owned and created by the Construction Specifications Institute (CSI) of the United States and Construction Specifications Canada (CSC) denoting a numerical system of organization for construction-related information and data, based on a 16-division format. mastic A thick bituminous-based adhesive used for applying floor and wall tiles. mat foundation A continuous thick-slab foundation supporting an entire structure. This type of foundation may be thickened or have holes in some areas and is typically used to distribute a buildingís weight over as wide an area as possible, especially if soil conditions are poor. matte A dull surface finish with low reflectance. mattress A grade-level concrete slab used to support equipment, such as transformers and air conditioning units, outside a building. maximum size of aggregates The maximum size of aggregate permitted in a concrete mix design determined by the thickness of slab, distance from the reinforcing steel to the face of the concrete, and the method of placement. MBH 1,000 Btuís per hour mechanic Any person skilled in a particular trade or craft. mechanical bond A bond formed by keying or interlocking as opposed to a chemical bond by adhesion, as plaster bonding to lath or concrete bonding to deformed reinforcing rods. mechanicís lien Generally, a mechanicís lien entitles the party who provided the goods and services to place a lien on the property which, like a mortgage, is a recognition of a debt that must be paid by the property owner within a prescribed time period. If it is not paid, the lien holder can sell the property and use the proceeds to pay the lien amount. meeting rail With a double-hung window, the horizontal rails which meet in the middle. member A general term for a structural component of a building, such as a beam or column. membrane curing A process of controlling the curing concrete by sealing in the moisture that would be lost to evaporation. The process is accomplished either by spraying a sealer on the surface or by covering the surface with a sheet film. membrane roofing A term that most commonly refers to a roof covering employing flexible elastomeric plastic materials from 35 to 60 mils thick, that is applied from rolls and has vulcanized joints. The initial cost of an elastomeric-membrane roof covering system is higher than a built-up roof, but the life cycle cost is lower. mercury vapor lamp An electric discharge lamp that produces a blue-white light by creating an arc in mercury vapor enclosed in a globe or tube. mesh A network of wire screening or welded wire fabric used in construction. metal halide lamp An electric-discharge lamp that produces light from a metal vapor such as mercury or sodium. metal wall ties The prefabricated metal strips that secure a masonry veneer to a structural wall. mezzanine A suspended floor, usually between the first floor and the ceiling, that covers less area than the floor below. mil A lineal measurement equal to 0.001 inch. millwork All the building products made of wood that are produced in a planing mill, such as moldings, door and window frames, doors, windows, blinds and stairs. mineral dust Aggregate passing the No. 200 screen, usually a by-product of crushed limestone or traprock. miter joint A joint, usually 90?, formed by joining two surfaces beveled at angles, usually 45? each. mix design The selection of specific materials and their proportions for a concrete or mortar batch, with the goal of achieving the required properties with the most economical use of materials. mixing box In HVAC systems a chamber, usually located upstream of the filters, that collects outside air and return air. mixing valve A valve that mixes two liquids or a liquid and a gas, such as steam with water or hot water with cold water. mock-up A model, either full size or to scale, of a construction system or assembly used to analyze construction details, strength, and appearance. Mock-ups are commonly used for masonry and exposed concrete construction projects. modular masonry unit A brick or block manufactured to a modular dimension of 4". moisture barrier A dampproof course or vapor barrier, but not necessarily waterproof. moisture content The weight of water in materials such as wood, soil, masonry units, or roofing materials, expressed as a percentage of the total dry weight. moisture migration The movement of moisture through the components of a building system such as a floor or wall. The direction or the movement is always from high-humidity areas to low-humidity areas. molding An ornamental strip of material used at joints, cornices, bases, door and window trim, and the like, and most commonly made of wood, plaster, plastic, or metal. moment An applied load or force which creates bending in a structural member. moment connection A rigid connection between structural members which transfers moment from one member to the other, and thus resists the moment force. A pinned connection cannot resist moment forces, only shear forces. monolithic concrete Concrete that has been cast continuously with no joints other than construction joints. mortar A plastic mixture used in masonry construction that can be troweled and hardens in place. The most common materials that mortar may contain are Portland, hydraulic, or mortar cement, lime, fine aggregate, and water. mortar bed A layer of fresh mortar into which a structural member or flooring is set. mortise A recess cut in one member, usually wood, to receive a tenon from another member. mortise and tenon joint A joint between two members, usually wood, which incorporates one or more tenons on one member fitting into mortises in the other member. Used on joints such as door stiles, door rails, window sashes, and cabinetry. mud slab A base slab of low-strength concrete from 2" to 6" thick placed over a wet subbase before placing a concrete footing or grade slab. mudjacking A method of raising a depressed concrete highway slab or slab-on-grade by boring holes at selected locations and pumping in grout or liquid asphalt. mullion The vertical member separating the panels or glass lights of a window or door system. multizone system An air conditioning system that is capable of handling several individual zones simultaneously. muntin A short vertical or horizontal bar used to separate panes of glass in a window or panels in a door. The muntin extends from a stile, rail, or bar to another bar. Search Again