Glossary: B


Back BlockingA short piece of gypsum board adhesively laminated behind the joints between each framing member to reinforce the joint.
BackfillEarth filled in around a foundation wall to replace earth removed for construction of the foundation.
Backup StripsPieces of wood nailed at the ceiling-sidewall corner to provide fastening for ends of plaster base or gypsum panels.
BallastAn electrical device to provide the starting voltage and operating current for fluorescent, mercury, and other electric discharge lamps.
Balloon FrameMethod of framing outside walls in which studs extend the full length or height of the wall.
Bank MeasureThe volume of soil in situ in cubic yards.
Bar JoistOpen-web, flat truss structural member used to support floor or roof structure. Web section is made from bar or rod stock, and chords are usually fabricated from “T” or angle sections.
Barrier-FreeThe absense of environmental barriers, permitting free access and circulation by the handicapped.
BatchThe amount of concrete mixed at one time.
BattenNarrow strip of wood, plastic, metal or gypsum board used to conceal an open joint.
BauxiteOre containing high percentages of aluminum oxide.
BCMCBoard for the Coordination of Model Codes; part of the Council of American Building Officials Association (CABO).
BeamA straight horizontal structural loadbearing member spanning a distance between supports.
BearingSupport area upon which something rests, such as the point on bearing walls where the weight of the floor joist or roof rafter bears.
Bearing CapacityThe ability of a soil to support load.
Bearing PileA pile that carries a vertical load.
Bearing PlateA steel plate placed under a beam, column, or truss to distribute the end reaction from the beam to the supporting member.
Bearing WallA wall that supports any vertical load in addition to it’s own weight.
BedTo set firmly and permanently in place.
BedrockThe hard, solid rock formation at or below the surface of the earth.
Bench MarkA relatively permanent point of known location and elevation.
BendingBowing of a member that results when a load or loads are applied laterally between supports.
Bending MomentThe algebraic sum of the moments of all forces that are on one side of a give cross-section of a beam.
Bending StressA compressive or tensile stress developed by applying non-axial force to structural members.
BeneficationA process of grinding and concentration that removes unwanted elements from iron-ore before the ore is used to produce steel.
Bentonite ClayAn absorptive clay that swells several times its dry volume when saturated with water.
BermA convex shapeed bank of earth.
BinderFilm-forming ingredient in paint that binds the suspended pigment particles together.
BitumenA generic term describing a material that is a mixture of predominantly hydrocarbons in solid or viscous form. It is derived from coal and petroleum.
Bitumenous CoatingCoating formulated by dissolving natural bitumens in an organic solvent.
BleedingExcess water that rises to the surface of concrete shortly after it has been poured.
BlockingWood pieces inserted between joists, studs, rafters, and other structural members to stabilize the frame, provide a nailing surface for finish materials, and block the passage of fire between the members.
Board Foot (Bd. Ft.)Volume of a piece of wood, nominal 19 x 129 x 18. All lumber is sold by the board-foot measure.
BoardsLumber less than 2 inches (50.8 mm) thick and 1 inch (25.4 mm) or greater in width.
BoilerA closed vessel used to produce hot water or steam.
Bond BeamA continuous reinforced beam formed from horizontal masonry members bonded with reinforced concrete.
Bond BreakerA material used to prevent adjoining materials from adhering.
Bonding AgentA compound that will hold materials together by bonding to the surfaces to be joined.
BoundaryThe legal recorded property line between two parcels of land.
Box BeamA structural member of metal or plywood whose cross-section is a closed rectangular box shape.
Box SillA type of sill used in frame construction in which the floor joists butt and are nailed to a header joist and rest on the sill.
Braced FrameA vertical truss used to resist lateral forces.
BranchA pipe in a plumbing system into which no other branch pipes discharge and that discharges into a main or submain.
Branch CircuitThe electrical wiring between the overcurrent protection device and the connected outlets.
Branch IntervalA length of soil or waste stack 8 feet or more in height (equal to one story) within which the horizontal branches from one floor or story of a building are connected to a stack.
Branch VentA vent connecting one or more individual vents into a vent stack or stack vent.
Branch, PlumbingA horizontal run of waste piping that carries waste material to a vertical riser.
Breaking StrengthThe point at which a material actually begins to break.
Brick VeneerNon-loadbearing brick facing applied to a wall to give appearance of solid-brick construction; bricks are fastened to backup structure with metal ties embedded in mortar joints.
BridgingMembers attached between floor joists to distribute concentrated loads over more than one joist and to prevent rotation of the joist. Solid bridging consists of joist-depth lumber installed perpendicular to and between the joists. Cross-bridging consists of pairs of braces set in an “X” form between joists.
Brinell HardnessA measure of the resistance of a material to indentation.
Brinnel Hardness NumberA measure of Brinell hardness that is obtained by dividing the load in kilograms by the area of the indentation given in square millimeters.
British Thermal Unit (BTU)The amount of heat required to raise the temperature of 1 pound (lb) of water by 1 degree Fahrenheit (F).
BrittlenessThe characteristic of a material that tends to crack or break without appreciable plastic deformation.
Brown CoatThe second coat of plaster in a three-coat plaster finish.
Buffer ZoneAn area separating two different elements or functions.
Buffer, ElevatorEnergy-absorbing units placed in the elevator pit.
Buildable AreaThe net ground area of a lot that can be covered by a building after required setbacks and other zoning limitations have been accounted for.
Building CodeA set of legal regulations that ensure a minimum standard of health and safety in buildings.
Building DrainThe lowest horizontal piping of a plumbing drainage system that receives the discharge from soil, waste, and other drainage pipes within the building and carries the wasted to the building sewer.
Building EnvelopeThe enclosure that contains a building’s maximum volume.
Building LineA defined limit within a property line beyond which a structure may not protrude.
Building SewerHorizontal piping that carries the waste discharge from the building drain to the public sewer or septic tank.
Built-Up Roof MembraneA continuous, semi-flexible roof membrane built up fo plies of saturated felts, coated felts, fabrics, or mats that have surface coats of bitumens. The last ply is covered with mineral aggregates, bituminous materials, or a granular-surface roofing sheet.
BurningCuring bricks by placing them in a kiln and subjecting them to a high temperature.
BusA rigid electric conductor enclosed in a protective busway.
BuswayA rigid conduit used to protect a bus running through it.
BX CableA cable sheathed with spirally wrapped metal strip identified as Type AC.