Glossary of Construction Terminology



Back Charge – A billing for work performed or costs incurred by one party that, in accordance with the agreement should have been performed or incurred by the party to whom billed, i.e. clean-up work, a tub chip or broken window, Owners back charge general contractors, and general contractors back charge subcontractors.

backfill – Filling in any previously excavated area.

backflow – The flow of liquids through irrigation into the pipes of a water supply from any source which is opposite to the intended direction of flow.

backflow preventer – A device or means to prevent backflow into the water supply.

backhoe – Self powered excavation equipment that digs by pulling a boom mounted bucket towards itself. It is used to dig basements and/or footings and to install drainage or sewer systems.

ballast – A transformer that steps up the voltage in a florescent lamp.

balusters – Vertical members in a railing used between a top rail and bottom rail or the stair treads. Sometimes referred to as pickets or spindles.

barrel roof – A roof design which in cross section is arched.

base molding – Molding used to trim the upper edge of interior baseboard.

base shoe – Molding used next to the floor on interior base board. Sometimes called a carpet strip.

batten – Narrow strips of wood used to cover joints or as decorative vertical members over plywood or wide boards.

batt insulation – Strips of insulation – usually fiberglass, that fit between studs or other framing.

bead – In glazing, an applied sealant in a joint irrespective of the method of application, such as caulking bead, glazing bead, etc. Also a molding or stop used to hold glass or panels in position.

beam – A structural member transversely supporting a load.

bearing wall - A wall that supports any vertical load in addition to its own weight.

below grade – The portion of a building that is below ground level.

bid bond – Security posted by a bidder to ensure performance in accordance with a bid.

bidding – Getting prices from various contractors and/or subcontractors.

bid documents – Drawings, details, and specifications for a particular project.

bleeding – A migration of a liquid to the surface of a component or into/onto an adjacent material.

blister – An enclosed raised spot evident on the surface of a building. They are mainly caused by the expansion of trapped air, water vapor, moisture or other gases.

blocking- Small wood pieces to brace framing members or to provide a nailing base for gypsum board or paneling.

blue prints – Architectural plans for a building or construction project which are likely to include floor plans, footing and foundation plans, elevations, plot plans and various other schedules or details.

board foot – In carpentry, the equivalent of a board one foot square and one inch thick.

bond breaker – A substance or a tape applied between two adjoining materials to prevent adhesion.

bottom plate – The "2 x 4's or 6's" that lay on the subfloor upon which the vertical studs are installed, also called the sole plate.

brace – An inclined piece of framing lumber applied to wall or floor to strengthen the structure. Often used on walls as temporary bracing until framing has been completed.

bracing – Ties and rods used for supporting and strengthening various parts of a building, used for lateral stability for columns and beams.

brake metal – Sheet metal that has been bent to the desired configuration.

breaker panel – The electrical service box that distributes electrical power to entering the home to each branch circuit. Each branch circuit is attached to a circuit breaker.

brown coat – The coat of plaster directly beneath the finish coat. In three-coat work, the brown coat is the second coat.

BTU – British Thermal Unit. The amount of heat energy required to raise the temperature of one pound of water through a change of one degree F.

bubbling - In glazing, open or closed pockets of sealant caused by release, production or expansion of gasses.

Building Permit – Written authorization from the city, county or other governing regulatory body giving permission to construct or renovate a building. A building permit is specific to the building project described in the application.

Building Codes – Community ordinances governing the manner in which a building may be constructed or modified.

Building Insurance – Insurance covering the structure of the building.

buttering - In glazing, application of sealant or compound to the flat surface of some member before placing the member in position, such as buttering of a removable stop before fastening the stop in place.

butt glazing – The installation of glass products where the vertical glass edges are without structural supporting mullions.

butt joint – The junction where the ends of two timbers or other members meet in a square-cut joint.

BX. Armored cable – A factory assembly of insulated conductors inside a flexible metal covering. It can be, except where exposed to excessive moisture, and should not be run below grade. It must always be grounded and uses its armor as an equipment ground.